64438940 has 24 divisors (see below), whose sum is σ = 138470640. Its totient is φ = 25175808.

The previous prime is 64438919. The next prime is 64438967. The reversal of 64438940 is 4983446.

It is a junction number, because it is equal to n+sod(n) for n = 64438894 and 64438903.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 36605 + ... + 38324.

It is an arithmetic number, because the mean of its divisors is an integer number (5769610).

Almost surely, 2^64438940 is an apocalyptic number.

It is an amenable number.

64438940 is an abundant number, since it is smaller than the sum of its proper divisors (74031700).

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

64438940 is a wasteful number, since it uses less digits than its factorization.

64438940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 74981 (or 74979 counting only the distinct ones).

The product of its (nonzero) digits is 82944, while the sum is 38.

The square root of 64438940 is about 8027.3868724511. The cubic root of 64438940 is about 400.9123756776.

The spelling of 64438940 in words is "sixty-four million, four hundred thirty-eight thousand, nine hundred forty".