1621135320 has 64 divisors (see below), whose sum is σ = 5558181120. Its totient is φ = 370545024.

The previous prime is 1621135319. The next prime is 1621135337. The reversal of 1621135320 is 235311261.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 964122 + ... + 965801.

It is an arithmetic number, because the mean of its divisors is an integer number (86846580).

Almost surely, 2^1621135320 is an apocalyptic number.

1621135320 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1621135320 is an abundant number, since it is smaller than the sum of its proper divisors (3937045800).

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

1621135320 is a wasteful number, since it uses less digits than its factorization.

1621135320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1929944 (or 1929940 counting only the distinct ones).

The product of its (nonzero) digits is 1080, while the sum is 24.

The square root of 1621135320 is about 40263.3247509443. The cubic root of 1621135320 is about 1174.7345880079.

Adding to 1621135320 its reverse (235311261), we get a palindrome (1856446581).

The spelling of 1621135320 in words is "one billion, six hundred twenty-one million, one hundred thirty-five thousand, three hundred twenty".