1640538297 has 12 divisors (see below), whose sum is σ = 2370054960. Its totient is φ = 1093512888.

The previous prime is 1640538257. The next prime is 1640538313. The reversal of 1640538297 is 7928350461.

1640538297 is digitally balanced in base 10, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 1640538297 - 2⁸ = 1640538041 is a prime.

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

1640538297 is strictly pandigital in base 10.

It is not an unprimeable number, because it can be changed into a prime (1640538217) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 66178 + ... + 87524.

It is an arithmetic number, because the mean of its divisors is an integer number (197504580).

It is a 2-persistent number, because it is pandigital, and so is 2⋅1640538297 = 3281076594, but 3⋅1640538297 = 4921614891 is not.

Almost surely, 2^1640538297 is an apocalyptic number.

1640538297 is the 25617-th heptagonal number.

It is an amenable number.

1640538297 is a deficient number, since it is larger than the sum of its proper divisors (729516663).

1640538297 is a wasteful number, since it uses less digits than its factorization.

1640538297 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29892 (or 29889 counting only the distinct ones).

The product of its (nonzero) digits is 362880, while the sum is 45.

The square root of 1640538297 is about 40503.5590658401. The cubic root of 1640538297 is about 1179.4027181686.

The spelling of 1640538297 in words is "one billion, six hundred forty million, five hundred thirty-eight thousand, two hundred ninety-seven".