64901023297921 has 4 divisors (see below), whose sum is σ = 64950908789844. Its totient is φ = 64851137806000.

The previous prime is 64901023297879. The next prime is 64901023297937. The reversal of 64901023297921 is 12979232010946.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 1254310401600 + 63646712896321 = 1119960^2 + 7977889^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-64901023297921 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (64901023297021) 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, 24942744010 + ... + 24942746611.

It is an arithmetic number, because the mean of its divisors is an integer number (16237727197461).

Almost surely, 2^{64901023297921} is an apocalyptic number.

It is an amenable number.

64901023297921 is a deficient number, since it is larger than the sum of its proper divisors (49885491923).

64901023297921 is a wasteful number, since it uses less digits than its factorization.

64901023297921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49885491922.

The product of its (nonzero) digits is 2939328, while the sum is 55.

The spelling of 64901023297921 in words is "sixty-four trillion, nine hundred one billion, twenty-three million, two hundred ninety-seven thousand, nine hundred twenty-one".