397987223138 has 6 divisors (see below), whose sum is σ = 596982172971. Its totient is φ = 198993165482.

The previous prime is 397987223113. The next prime is 397987223171. The reversal of 397987223138 is 831322789793.

It can be written as a sum of positive squares in only one way, i.e., 198993611569 + 198993611569 = 446087^2 + 446087^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=446087.

It is a Duffinian number.

It is an unprimeable number.

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 2 ways as a sum of consecutive naturals, for example, 669131 + ... + 1115217.

Almost surely, 2^397987223138 is an apocalyptic number.

397987223138 is a deficient number, since it is larger than the sum of its proper divisors (198994949833).

397987223138 is an frugal number, since it uses more digits than its factorization.

397987223138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 892176 (or 446089 counting only the distinct ones).

The product of its digits is 27433728, while the sum is 62.

The spelling of 397987223138 in words is "three hundred ninety-seven billion, nine hundred eighty-seven million, two hundred twenty-three thousand, one hundred thirty-eight".