390621738865 has 32 divisors (see below), whose sum is σ = 498493535904. Its totient is φ = 292827955200.

The previous prime is 390621738863. The next prime is 390621738887. The reversal of 390621738865 is 568837126093.

It can be written as a sum of positive squares in 16 ways, for example, as 56573573904 + 334048164961 = 237852^2 + 577969^2 .

It is not a de Polignac number, because 390621738865 - 2¹ = 390621738863 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (390621738863) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 72107637 + ... + 72113053.

It is an arithmetic number, because the mean of its divisors is an integer number (15577922997).

Almost surely, 2^390621738865 is an apocalyptic number.

It is an amenable number.

390621738865 is a deficient number, since it is larger than the sum of its proper divisors (107871797039).

390621738865 is a wasteful number, since it uses less digits than its factorization.

390621738865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8997.

The product of its (nonzero) digits is 13063680, while the sum is 58.

The spelling of 390621738865 in words is "three hundred ninety billion, six hundred twenty-one million, seven hundred thirty-eight thousand, eight hundred sixty-five".