63640613 has 4 divisors (see below), whose sum is σ = 65693568. Its totient is φ = 61587660.

The previous prime is 63640573. The next prime is 63640663. The reversal of 63640613 is 31604636.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-63640613 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (63640663) 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, 1026431 + ... + 1026492.

It is an arithmetic number, because the mean of its divisors is an integer number (16423392).

Almost surely, 2^63640613 is an apocalyptic number.

It is an amenable number.

63640613 is a deficient number, since it is larger than the sum of its proper divisors (2052955).

63640613 is a wasteful number, since it uses less digits than its factorization.

63640613 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2052954.

The product of its (nonzero) digits is 7776, while the sum is 29.

The square root of 63640613 is about 7977.5066906898. The cubic root of 63640613 is about 399.2498712298.

The spelling of 63640613 in words is "sixty-three million, six hundred forty thousand, six hundred thirteen".