398660785 has 16 divisors (see below), whose sum is σ = 485036496. Its totient is φ = 314523648.

The previous prime is 398660749. The next prime is 398660789. The reversal of 398660785 is 587066893.

It can be written as a sum of positive squares in 8 ways, for example, as 38837824 + 359822961 = 6232^2 + 18969^2 .

It is a cyclic number.

It is not a de Polignac number, because 398660785 - 2¹³ = 398652593 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (398660789) 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, 152449 + ... + 155041.

It is an arithmetic number, because the mean of its divisors is an integer number (30314781).

Almost surely, 2^398660785 is an apocalyptic number.

It is an amenable number.

398660785 is a deficient number, since it is larger than the sum of its proper divisors (86375711).

398660785 is a wasteful number, since it uses less digits than its factorization.

398660785 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3012.

The product of its (nonzero) digits is 2177280, while the sum is 52.

The square root of 398660785 is about 19966.4915546022. The cubic root of 398660785 is about 735.9830952964.

The spelling of 398660785 in words is "three hundred ninety-eight million, six hundred sixty thousand, seven hundred eighty-five".