397920722 has 4 divisors (see below), whose sum is σ = 596881086. Its totient is φ = 198960360.

The previous prime is 397920701. The next prime is 397920779. The reversal of 397920722 is 227029793.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 227029793 = 53 ⋅4283581.

It can be written as a sum of positive squares in only one way, i.e., 343027441 + 54893281 = 18521^2 + 7409^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 397920722.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99480179 + ... + 99480182.

Almost surely, 2^397920722 is an apocalyptic number.

397920722 is a deficient number, since it is larger than the sum of its proper divisors (198960364).

397920722 is a wasteful number, since it uses less digits than its factorization.

397920722 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 198960363.

The product of its (nonzero) digits is 95256, while the sum is 41.

The square root of 397920722 is about 19947.9503207723. The cubic root of 397920722 is about 735.5273935526.

The spelling of 397920722 in words is "three hundred ninety-seven million, nine hundred twenty thousand, seven hundred twenty-two".