1631157220 has 192 divisors, whose sum is σ = 4546160640. Its totient is φ = 476236800.

The previous prime is 1631157197. The next prime is 1631157221. The reversal of 1631157220 is 227511361.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is not an unprimeable number, because it can be changed into a prime (1631157221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 3130560 + ... + 3131080.

It is an arithmetic number, because the mean of its divisors is an integer number (23677920).

Almost surely, 2^1631157220 is an apocalyptic number.

1631157220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1631157220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2273080320).

1631157220 is an abundant number, since it is smaller than the sum of its proper divisors (2915003420).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1631157220 is a wasteful number, since it uses less digits than its factorization.

1631157220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 674 (or 672 counting only the distinct ones).

The product of its (nonzero) digits is 2520, while the sum is 28.

The square root of 1631157220 is about 40387.5874496113. The cubic root of 1631157220 is about 1177.1503631181.

Adding to 1631157220 its reverse (227511361), we get a palindrome (1858668581).

It can be divided in two parts, 1631 and 157220, that added together give a palindrome (158851).

The spelling of 1631157220 in words is "one billion, six hundred thirty-one million, one hundred fifty-seven thousand, two hundred twenty".