64681938 has 12 divisors (see below), whose sum is σ = 140144238. Its totient is φ = 21560640.

The previous prime is 64681931. The next prime is 64681949. The reversal of 64681938 is 83918646.

It can be written as a sum of positive squares in only one way, i.e., 58936329 + 5745609 = 7677^2 + 2397^2 .

It is a junction number, because it is equal to n+sod(n) for n = 64681893 and 64681902.

It is not an unprimeable number, because it can be changed into a prime (64681931) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1796703 + ... + 1796738.

Almost surely, 2^64681938 is an apocalyptic number.

64681938 is an abundant number, since it is smaller than the sum of its proper divisors (75462300).

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

64681938 is a wasteful number, since it uses less digits than its factorization.

64681938 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3593449 (or 3593446 counting only the distinct ones).

The product of its digits is 248832, while the sum is 45.

The square root of 64681938 is about 8042.5081908569. The cubic root of 64681938 is about 401.4156878256.

The spelling of 64681938 in words is "sixty-four million, six hundred eighty-one thousand, nine hundred thirty-eight".