64691844 has 48 divisors (see below), whose sum is σ = 172905600. Its totient is φ = 18441216.

The previous prime is 64691843. The next prime is 64691897. The reversal of 64691844 is 44819646.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a junction number, because it is equal to n+sod(n) for n = 64691796 and 64691805.

It is not an unprimeable number, because it can be changed into a prime (64691843) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 69172 + ... + 70100.

It is an arithmetic number, because the mean of its divisors is an integer number (3602200).

Almost surely, 2^64691844 is an apocalyptic number.

It is an amenable number.

64691844 is an abundant number, since it is smaller than the sum of its proper divisors (108213756).

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

64691844 is a wasteful number, since it uses less digits than its factorization.

64691844 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1772 (or 1770 counting only the distinct ones).

The product of its digits is 165888, while the sum is 42.

The square root of 64691844 is about 8043.1240199316. The cubic root of 64691844 is about 401.4361789702.

The spelling of 64691844 in words is "sixty-four million, six hundred ninety-one thousand, eight hundred forty-four".