1640422120 has 64 divisors (see below), whose sum is σ = 3824755200. Its totient is φ = 632459520.

The previous prime is 1640422117. The next prime is 1640422141. The reversal of 1640422120 is 212240461.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 1640422091 and 1640422100.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1148847 + ... + 1150273.

It is an arithmetic number, because the mean of its divisors is an integer number (59761800).

Almost surely, 2^1640422120 is an apocalyptic number.

1640422120 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 1640422120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1912377600).

1640422120 is an abundant number, since it is smaller than the sum of its proper divisors (2184333080).

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

1640422120 is a wasteful number, since it uses less digits than its factorization.

1640422120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2458 (or 2454 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 22.

The square root of 1640422120 is about 40502.1248825293. The cubic root of 1640422120 is about 1179.3748771637.

Adding to 1640422120 its reverse (212240461), we get a palindrome (1852662581).

The spelling of 1640422120 in words is "one billion, six hundred forty million, four hundred twenty-two thousand, one hundred twenty".