1640655025 has 9 divisors (see below), whose sum is σ = 2034663393. Its totient is φ = 1312362000.

The previous prime is 1640655017. The next prime is 1640655041. The reversal of 1640655025 is 5205560461.

The square root of 1640655025 is 40505.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 555874929 + 1084780096 = 23577^2 + 32936^2 .

It is not a de Polignac number, because 1640655025 - 2³ = 1640655017 is a prime.

It is a super-2 number, since 2×1640655025² = 5383497822115501250, which contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 198475 + ... + 206575.

Almost surely, 2^1640655025 is an apocalyptic number.

1640655025 is the 40505-th square number.

1640655025 is the 20253-rd centered octagonal number.

It is an amenable number.

1640655025 is a deficient number, since it is larger than the sum of its proper divisors (394008368).

1640655025 is an frugal number, since it uses more digits than its factorization.

1640655025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16212 (or 8106 counting only the distinct ones).

The product of its (nonzero) digits is 36000, while the sum is 34.

The cubic root of 1640655025 is about 1179.4306898930.

The spelling of 1640655025 in words is "one billion, six hundred forty million, six hundred fifty-five thousand, twenty-five".