398765646 has 16 divisors (see below), whose sum is σ = 886146000. Its totient is φ = 132921864.

The previous prime is 398765641. The next prime is 398765669. The reversal of 398765646 is 646567893.

398765646 is a `hidden beast` number, since 3 + 9 + 8 + 76 + 564 + 6 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54), and also a Moran number because the ratio is a prime number: 7384549 = 398765646 / (3 + 9 + 8 + 7 + 6 + 5 + 6 + 4 + 6).

It is a junction number, because it is equal to n+sod(n) for n = 398765592 and 398765601.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (398765641) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3692221 + ... + 3692328.

It is an arithmetic number, because the mean of its divisors is an integer number (55384125).

Almost surely, 2^398765646 is an apocalyptic number.

398765646 is an abundant number, since it is smaller than the sum of its proper divisors (487380354).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

398765646 is a wasteful number, since it uses less digits than its factorization.

398765646 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7384560 (or 7384554 counting only the distinct ones).

The product of its digits is 6531840, while the sum is 54.

The square root of 398765646 is about 19969.1173064810. The cubic root of 398765646 is about 736.0476189555.

The spelling of 398765646 in words is "three hundred ninety-eight million, seven hundred sixty-five thousand, six hundred forty-six".