390928961 has 4 divisors (see below), whose sum is σ = 404409300. Its totient is φ = 377448624.

The previous prime is 390928913. The next prime is 390928963. The reversal of 390928961 is 169829093.

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 198274561 + 192654400 = 14081^2 + 13880^2 .

It is a cyclic number.

It is not a de Polignac number, because 390928961 - 2⁶ = 390928897 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (390928963) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6740126 + ... + 6740183.

It is an arithmetic number, because the mean of its divisors is an integer number (101102325).

Almost surely, 2^390928961 is an apocalyptic number.

It is an amenable number.

390928961 is a deficient number, since it is larger than the sum of its proper divisors (13480339).

390928961 is a wasteful number, since it uses less digits than its factorization.

390928961 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13480338.

The product of its (nonzero) digits is 209952, while the sum is 47.

The square root of 390928961 is about 19771.9235533622. The cubic root of 390928961 is about 731.1939933632.

The spelling of 390928961 in words is "three hundred ninety million, nine hundred twenty-eight thousand, nine hundred sixty-one".