65261664 has 72 divisors (see below), whose sum is σ = 199875312. Its totient is φ = 20079360.

The previous prime is 65261641. The next prime is 65261671. The reversal of 65261664 is 46616256.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (72).

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4972 + ... + 12459.

It is an arithmetic number, because the mean of its divisors is an integer number (2776046).

Almost surely, 2^65261664 is an apocalyptic number.

It is an amenable number.

65261664 is an abundant number, since it is smaller than the sum of its proper divisors (134613648).

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

65261664 is a wasteful number, since it uses less digits than its factorization.

65261664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17460 (or 17449 counting only the distinct ones).

The product of its digits is 51840, while the sum is 36.

The square root of 65261664 is about 8078.4691619143. The cubic root of 65261664 is about 402.6113812865.

The spelling of 65261664 in words is "sixty-five million, two hundred sixty-one thousand, six hundred sixty-four".