390395421 has 12 divisors (see below), whose sum is σ = 607281948. Its totient is φ = 240243264.

The previous prime is 390395407. The next prime is 390395437. The reversal of 390395421 is 124593093.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 134235396 + 256160025 = 11586^2 + 16005^2 .

It is not a de Polignac number, because 390395421 - 2¹³ = 390387229 is a prime.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (390395471) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1668240 + ... + 1668473.

It is an arithmetic number, because the mean of its divisors is an integer number (50606829).

Almost surely, 2^390395421 is an apocalyptic number.

It is an amenable number.

390395421 is a deficient number, since it is larger than the sum of its proper divisors (216886527).

390395421 is a wasteful number, since it uses less digits than its factorization.

390395421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3336732 (or 3336729 counting only the distinct ones).

The product of its (nonzero) digits is 29160, while the sum is 36.

The square root of 390395421 is about 19758.4265820940. The cubic root of 390395421 is about 730.8611973004.

The spelling of 390395421 in words is "three hundred ninety million, three hundred ninety-five thousand, four hundred twenty-one".