390021247 has 16 divisors (see below), whose sum is σ = 493115904. Its totient is φ = 299628000.

The previous prime is 390021197. The next prime is 390021253. The reversal of 390021247 is 742120093.

It is not a de Polignac number, because 390021247 - 2¹⁵ = 389988479 is a prime.

It is a super-2 number, since 2×390021247² = 304233146222870018, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (390031247) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 30204 + ... + 41137.

It is an arithmetic number, because the mean of its divisors is an integer number (30819744).

Almost surely, 2^390021247 is an apocalyptic number.

390021247 is a deficient number, since it is larger than the sum of its proper divisors (103094657).

390021247 is a wasteful number, since it uses less digits than its factorization.

390021247 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71430.

The product of its (nonzero) digits is 3024, while the sum is 28.

The square root of 390021247 is about 19748.9555926383. The cubic root of 390021247 is about 730.6276249972.

The spelling of 390021247 in words is "three hundred ninety million, twenty-one thousand, two hundred forty-seven".