394884721 has 16 divisors (see below), whose sum is σ = 521285760. Its totient is φ = 289601280.

The previous prime is 394884719. The next prime is 394884767. The reversal of 394884721 is 127488493.

It is a cyclic number.

It is not a de Polignac number, because 394884721 - 2¹ = 394884719 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (394884221) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 149526 + ... + 152143.

It is an arithmetic number, because the mean of its divisors is an integer number (32580360).

Almost surely, 2^394884721 is an apocalyptic number.

It is an amenable number.

394884721 is a deficient number, since it is larger than the sum of its proper divisors (126401039).

394884721 is a wasteful number, since it uses less digits than its factorization.

394884721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 301704.

The product of its digits is 387072, while the sum is 46.

The square root of 394884721 is about 19871.7065447334. The cubic root of 394884721 is about 733.6520072056.

It can be divided in two parts, 394884 and 721, that added together give a triangular number (395605 = T₈₈₉).

The spelling of 394884721 in words is "three hundred ninety-four million, eight hundred eighty-four thousand, seven hundred twenty-one".