3640624273721 has 2 divisors, whose sum is σ = 3640624273722. Its totient is φ = 3640624273720.

The previous prime is 3640624273661. The next prime is 3640624273817. The reversal of 3640624273721 is 1273724260463.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3610516818496 + 30107455225 = 1900136^2 + 173515^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-3640624273721 is a prime.

It is not a weakly prime, because it can be changed into another prime (3640624273021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1820312136860 + 1820312136861.

It is an arithmetic number, because the mean of its divisors is an integer number (1820312136861).

Almost surely, 2^{3640624273721} is an apocalyptic number.

It is an amenable number.

3640624273721 is a deficient number, since it is larger than the sum of its proper divisors (1).

3640624273721 is an equidigital number, since it uses as much as digits as its factorization.

3640624273721 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2032128, while the sum is 47.

The spelling of 3640624273721 in words is "three trillion, six hundred forty billion, six hundred twenty-four million, two hundred seventy-three thousand, seven hundred twenty-one".