64947877309 has 4 divisors (see below), whose sum is σ = 74226145504. Its totient is φ = 55669609116.

The previous prime is 64947877297. The next prime is 64947877373. The reversal of 64947877309 is 90377874946.

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 a de Polignac number, because none of the positive numbers 2^k-64947877309 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64947877009) 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, 4639134087 + ... + 4639134100.

It is an arithmetic number, because the mean of its divisors is an integer number (18556536376).

Almost surely, 2^64947877309 is an apocalyptic number.

It is an amenable number.

64947877309 is a deficient number, since it is larger than the sum of its proper divisors (9278268195).

64947877309 is an equidigital number, since it uses as much as digits as its factorization.

64947877309 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9278268194.

The product of its (nonzero) digits is 64012032, while the sum is 64.

The spelling of 64947877309 in words is "sixty-four billion, nine hundred forty-seven million, eight hundred seventy-seven thousand, three hundred nine".