1640157968 has 20 divisors (see below), whose sum is σ = 3315972288. Its totient is φ = 784423200.

The previous prime is 1640157931. The next prime is 1640157979. The reversal of 1640157968 is 8697510461.

It is a Smith number, since the sum of its digits (47) coincides with the sum of the digits of its prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2228108 + ... + 2228843.

Almost surely, 2^1640157968 is an apocalyptic number.

It is an amenable number.

1640157968 is an abundant number, since it is smaller than the sum of its proper divisors (1675814320).

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

1640157968 is a wasteful number, since it uses less digits than its factorization.

1640157968 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4456982 (or 4456976 counting only the distinct ones).

The product of its (nonzero) digits is 362880, while the sum is 47.

The square root of 1640157968 is about 40498.8637865311. The cubic root of 1640157968 is about 1179.3115700933.

The spelling of 1640157968 in words is "one billion, six hundred forty million, one hundred fifty-seven thousand, nine hundred sixty-eight".