398177681 has 4 divisors (see below), whose sum is σ = 434375664. Its totient is φ = 361979700.

The previous prime is 398177603. The next prime is 398177701. The reversal of 398177681 is 186771893.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 398177681 - 2¹⁰ = 398176657 is a prime.

It is a super-2 number, since 2×398177681² = 317090931293075522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (398177581) 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, 18098975 + ... + 18098996.

It is an arithmetic number, because the mean of its divisors is an integer number (108593916).

Almost surely, 2^398177681 is an apocalyptic number.

It is an amenable number.

398177681 is a deficient number, since it is larger than the sum of its proper divisors (36197983).

398177681 is a wasteful number, since it uses less digits than its factorization.

398177681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36197982.

The product of its digits is 508032, while the sum is 50.

The square root of 398177681 is about 19954.3900182391. The cubic root of 398177681 is about 735.6856828006.

The spelling of 398177681 in words is "three hundred ninety-eight million, one hundred seventy-seven thousand, six hundred eighty-one".