64312661 has 4 divisors (see below), whose sum is σ = 73500192. Its totient is φ = 55125132.

The previous prime is 64312657. The next prime is 64312709. The reversal of 64312661 is 16621346.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 64312661 - 2² = 64312657 is a prime.

It is a super-2 number, since 2×64312661² = 8272236729801842, which contains 22 as substring.

It is a Duffinian number.

It is a nialpdrome in base 4.

It is a zygodrome in base 4.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64312961) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4593755 + ... + 4593768.

It is an arithmetic number, because the mean of its divisors is an integer number (18375048).

Almost surely, 2^64312661 is an apocalyptic number.

It is an amenable number.

64312661 is a deficient number, since it is larger than the sum of its proper divisors (9187531).

64312661 is an equidigital number, since it uses as much as digits as its factorization.

64312661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9187530.

The product of its digits is 5184, while the sum is 29.

The square root of 64312661 is about 8019.5175041894. The cubic root of 64312661 is about 400.6503192226.

The spelling of 64312661 in words is "sixty-four million, three hundred twelve thousand, six hundred sixty-one".