61564765 has 8 divisors (see below), whose sum is σ = 73946808. Its totient is φ = 49205760.

The previous prime is 61564733. The next prime is 61564787. The reversal of 61564765 is 56746516.

It can be written as a sum of positive squares in 4 ways, for example, as 7601049 + 53963716 = 2757^2 + 7346^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 61564765 - 2⁵ = 61564733 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 805 + ... + 11125.

It is an arithmetic number, because the mean of its divisors is an integer number (9243351).

Almost surely, 2^61564765 is an apocalyptic number.

It is an amenable number.

61564765 is a deficient number, since it is larger than the sum of its proper divisors (12382043).

61564765 is a wasteful number, since it uses less digits than its factorization.

61564765 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11519.

The product of its digits is 151200, while the sum is 40.

The square root of 61564765 is about 7846.3217497118. The cubic root of 61564765 is about 394.8608493461.

The spelling of 61564765 in words is "sixty-one million, five hundred sixty-four thousand, seven hundred sixty-five".