64405944 has 24 divisors (see below), whose sum is σ = 174432960. Its totient is φ = 21468624.

The previous prime is 64405927. The next prime is 64405949. The reversal of 64405944 is 44950446.

64405944 is a `hidden beast` number, since 64 + 4 + 0 + 594 + 4 = 666.

It is a tau number, because it is divible by the number of its divisors (24).

It is a super-2 number, since 2×64405944² = 8296251245062272, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 64405899 and 64405908.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64405949) 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, 447192 + ... + 447335.

It is an arithmetic number, because the mean of its divisors is an integer number (7268040).

Almost surely, 2^64405944 is an apocalyptic number.

It is an amenable number.

64405944 is an abundant number, since it is smaller than the sum of its proper divisors (110027016).

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

64405944 is a wasteful number, since it uses less digits than its factorization.

64405944 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 894539 (or 894532 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 36.

The square root of 64405944 is about 8025.3313950266. The cubic root of 64405944 is about 400.8439348494.

The spelling of 64405944 in words is "sixty-four million, four hundred five thousand, nine hundred forty-four".