65400779 has 4 divisors (see below), whose sum is σ = 65431080. Its totient is φ = 65370480.

The previous prime is 65400749. The next prime is 65400787. The reversal of 65400779 is 97700456.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 65400779 - 2²⁴ = 48623563 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (65400739) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11642 + ... + 16319.

It is an arithmetic number, because the mean of its divisors is an integer number (16357770).

Almost surely, 2^65400779 is an apocalyptic number.

65400779 is a deficient number, since it is larger than the sum of its proper divisors (30301).

65400779 is a wasteful number, since it uses less digits than its factorization.

65400779 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30300.

The product of its (nonzero) digits is 52920, while the sum is 38.

The square root of 65400779 is about 8087.0748110797. The cubic root of 65400779 is about 402.8972537193.

The spelling of 65400779 in words is "sixty-five million, four hundred thousand, seven hundred seventy-nine".