397140826 has 4 divisors (see below), whose sum is σ = 595711242. Its totient is φ = 198570412.

The previous prime is 397140823. The next prime is 397140857. The reversal of 397140826 is 628041793.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 628041793 = 5179 ⋅121267.

It can be written as a sum of positive squares in only one way, i.e., 388050601 + 9090225 = 19699^2 + 3015^2 .

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (397140823) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99285205 + ... + 99285208.

Almost surely, 2^397140826 is an apocalyptic number.

397140826 is a deficient number, since it is larger than the sum of its proper divisors (198570416).

397140826 is a wasteful number, since it uses less digits than its factorization.

397140826 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 198570415.

The product of its (nonzero) digits is 72576, while the sum is 40.

The square root of 397140826 is about 19928.3924590018. The cubic root of 397140826 is about 735.0465523448.

The spelling of 397140826 in words is "three hundred ninety-seven million, one hundred forty thousand, eight hundred twenty-six".