394966921 has 8 divisors (see below), whose sum is σ = 410347080. Its totient is φ = 379704192.

The previous prime is 394966919. The next prime is 394966931. The reversal of 394966921 is 129669493.

It can be written as a sum of positive squares in 4 ways, for example, as 2134521 + 392832400 = 1461^2 + 19820^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 394966921 - 2¹ = 394966919 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (394966931) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 22470 + ... + 35983.

It is an arithmetic number, because the mean of its divisors is an integer number (51293385).

Almost surely, 2^394966921 is an apocalyptic number.

It is an amenable number.

394966921 is a deficient number, since it is larger than the sum of its proper divisors (15380159).

394966921 is a wasteful number, since it uses less digits than its factorization.

394966921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58715.

The product of its digits is 629856, while the sum is 49.

The square root of 394966921 is about 19873.7747043686. The cubic root of 394966921 is about 733.7029098343.

The spelling of 394966921 in words is "three hundred ninety-four million, nine hundred sixty-six thousand, nine hundred twenty-one".