394297881 has 32 divisors (see below), whose sum is σ = 568425600. Its totient is φ = 242221056.

The previous prime is 394297877. The next prime is 394297933. The reversal of 394297881 is 188792493.

It is not a de Polignac number, because 394297881 - 2² = 394297877 is a prime.

It is a super-2 number, since 2×394297881² = 310941637922180322, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (51).

It is not an unprimeable number, because it can be changed into a prime (394297801) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 877945 + ... + 878393.

It is an arithmetic number, because the mean of its divisors is an integer number (17763300).

Almost surely, 2^394297881 is an apocalyptic number.

It is an amenable number.

394297881 is a deficient number, since it is larger than the sum of its proper divisors (174127719).

394297881 is a wasteful number, since it uses less digits than its factorization.

394297881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 793.

The product of its digits is 870912, while the sum is 51.

The square root of 394297881 is about 19856.9353375590. The cubic root of 394297881 is about 733.2883991522.

The spelling of 394297881 in words is "three hundred ninety-four million, two hundred ninety-seven thousand, eight hundred eighty-one".