6640626535 has 4 divisors (see below), whose sum is σ = 7968751848. Its totient is φ = 5312501224.

The previous prime is 6640626533. The next prime is 6640626557. The reversal of 6640626535 is 5356260466.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 6640626535 - 2¹ = 6640626533 is a prime.

It is a super-2 number, since 2×6640626535² = 88195841554692212450, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 6640626491 and 6640626500.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6640626533) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 664062649 + ... + 664062658.

It is an arithmetic number, because the mean of its divisors is an integer number (1992187962).

Almost surely, 2^6640626535 is an apocalyptic number.

6640626535 is a deficient number, since it is larger than the sum of its proper divisors (1328125313).

6640626535 is a wasteful number, since it uses less digits than its factorization.

6640626535 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1328125312.

The product of its (nonzero) digits is 777600, while the sum is 43.

The square root of 6640626535 is about 81490.0394833626. The cubic root of 6640626535 is about 1879.6183900826.

The spelling of 6640626535 in words is "six billion, six hundred forty million, six hundred twenty-six thousand, five hundred thirty-five".