396921819 has 16 divisors (see below), whose sum is σ = 610824960. Its totient is φ = 224565600.

The previous prime is 396921803. The next prime is 396921859. The reversal of 396921819 is 918129693.

396921819 = 1712² + 1713² + ... + 1837².

It is not a de Polignac number, because 396921819 - 2⁴ = 396921803 is a prime.

It is a super-2 number, since 2×396921819² = 315093860796537522, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (396921859) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 91449 + ... + 95690.

It is an arithmetic number, because the mean of its divisors is an integer number (38176560).

Almost surely, 2^396921819 is an apocalyptic number.

396921819 is a deficient number, since it is larger than the sum of its proper divisors (213903141).

396921819 is a wasteful number, since it uses less digits than its factorization.

396921819 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 187250.

The product of its digits is 209952, while the sum is 48.

The square root of 396921819 is about 19922.8968526166. The cubic root of 396921819 is about 734.9114114156.

The spelling of 396921819 in words is "three hundred ninety-six million, nine hundred twenty-one thousand, eight hundred nineteen".