399897523 has 4 divisors (see below), whose sum is σ = 400406440. Its totient is φ = 399388608.

The previous prime is 399897521. The next prime is 399897529. The reversal of 399897523 is 325798993.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 325798993 = 13 ⋅25061461.

It is a cyclic number.

It is not a de Polignac number, because 399897523 - 2¹ = 399897521 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (399897521) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 253278 + ... + 254851.

It is an arithmetic number, because the mean of its divisors is an integer number (100101610).

Almost surely, 2^399897523 is an apocalyptic number.

399897523 is a deficient number, since it is larger than the sum of its proper divisors (508917).

399897523 is an equidigital number, since it uses as much as digits as its factorization.

399897523 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 508916.

The product of its digits is 3674160, while the sum is 55.

The square root of 399897523 is about 19997.4379108925. The cubic root of 399897523 is about 736.7433729380.

The spelling of 399897523 in words is "three hundred ninety-nine million, eight hundred ninety-seven thousand, five hundred twenty-three".