399979197 has 6 divisors (see below), whose sum is σ = 577747742. Its totient is φ = 266652792.

The previous prime is 399979193. The next prime is 399979199. The reversal of 399979197 is 791979993.

It can be written as a sum of positive squares in only one way, i.e., 358685721 + 41293476 = 18939^2 + 6426^2 .

It is not a de Polignac number, because 399979197 - 2² = 399979193 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (399979193) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 22221058 + ... + 22221075.

Almost surely, 2^399979197 is an apocalyptic number.

It is an amenable number.

399979197 is a deficient number, since it is larger than the sum of its proper divisors (177768545).

399979197 is a wasteful number, since it uses less digits than its factorization.

399979197 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44442139 (or 44442136 counting only the distinct ones).

The product of its digits is 8680203, while the sum is 63.

The square root of 399979197 is about 19999.4799182379. The cubic root of 399979197 is about 736.7935263554.

It can be divided in two parts, 39997 and 9197, that added together give a palindrome (49194).

The spelling of 399979197 in words is "three hundred ninety-nine million, nine hundred seventy-nine thousand, one hundred ninety-seven".