64400634 has 24 divisors (see below), whose sum is σ = 140348052. Its totient is φ = 21341760.

The previous prime is 64400617. The next prime is 64400659. The reversal of 64400634 is 43600446.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 64400625 + 9 = 8025^2 + 3^2 .

It is a junction number, because it is equal to n+sod(n) for n = 64400598 and 64400607.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7227 + ... + 13454.

Almost surely, 2^64400634 is an apocalyptic number.

64400634 is an abundant number, since it is smaller than the sum of its proper divisors (75947418).

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

64400634 is a wasteful number, since it uses less digits than its factorization.

64400634 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20862 (or 20859 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 27.

The square root of 64400634 is about 8025.0005607476. Note that the first 3 decimals coincide. The cubic root of 64400634 is about 400.8329185794.

The spelling of 64400634 in words is "sixty-four million, four hundred thousand, six hundred thirty-four".