640900700 has 54 divisors (see below), whose sum is σ = 1528709448. Its totient is φ = 233050400.

The previous prime is 640900661. The next prime is 640900739. The reversal of 640900700 is 7009046.

It is an interprime number because it is at equal distance from previous prime (640900661) and next prime (640900739).

It is a self number, because there is not a number n which added to its sum of digits gives 640900700.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 14384 + ... + 38583.

Almost surely, 2^640900700 is an apocalyptic number.

It is an amenable number.

640900700 is an abundant number, since it is smaller than the sum of its proper divisors (887808748).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

640900700 is a wasteful number, since it uses less digits than its factorization.

640900700 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53003 (or 52985 counting only the distinct ones).

The product of its (nonzero) digits is 1512, while the sum is 26.

The square root of 640900700 is about 25316.0166692946. The cubic root of 640900700 is about 862.1779572044.

Adding to 640900700 its reverse (7009046), we get a palindrome (647909746).

The spelling of 640900700 in words is "six hundred forty million, nine hundred thousand, seven hundred".