6640515477 has 24 divisors (see below), whose sum is σ = 9761588928. Its totient is φ = 4349116800.

The previous prime is 6640515473. The next prime is 6640515521. The reversal of 6640515477 is 7745150466.

6640515477 is a `hidden beast` number, since 6 + 64 + 0 + 515 + 4 + 77 = 666.

It is not a de Polignac number, because 6640515477 - 2² = 6640515473 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6640515473) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 162477 + ... + 199197.

It is an arithmetic number, because the mean of its divisors is an integer number (406732872).

Almost surely, 2^6640515477 is an apocalyptic number.

It is an amenable number.

6640515477 is a deficient number, since it is larger than the sum of its proper divisors (3121073451).

6640515477 is a wasteful number, since it uses less digits than its factorization.

6640515477 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37081 (or 37078 counting only the distinct ones).

The product of its (nonzero) digits is 705600, while the sum is 45.

The square root of 6640515477 is about 81489.3580598105. The cubic root of 6640515477 is about 1879.6079117630.

The spelling of 6640515477 in words is "six billion, six hundred forty million, five hundred fifteen thousand, four hundred seventy-seven".