621857394 has 48 divisors (see below), whose sum is σ = 1410057792. Its totient is φ = 197692704.

The previous prime is 621857377. The next prime is 621857459. The reversal of 621857394 is 493758126.

621857394 is a `hidden beast` number, since 62 + 18 + 573 + 9 + 4 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 152409 + ... + 156435.

It is an arithmetic number, because the mean of its divisors is an integer number (29376204).

Almost surely, 2^621857394 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 621857394, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (705028896).

621857394 is an abundant number, since it is smaller than the sum of its proper divisors (788200398).

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

621857394 is a wasteful number, since it uses less digits than its factorization.

621857394 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4431 (or 4428 counting only the distinct ones).

The product of its digits is 362880, while the sum is 45.

The square root of 621857394 is about 24937.0686729615. The cubic root of 621857394 is about 853.5525566252.

The spelling of 621857394 in words is "six hundred twenty-one million, eight hundred fifty-seven thousand, three hundred ninety-four".