621996686 has 4 divisors (see below), whose sum is σ = 932995032. Its totient is φ = 310998342.

The previous prime is 621996653. The next prime is 621996737. The reversal of 621996686 is 686699126.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 155499170 + ... + 155499173.

It is an arithmetic number, because the mean of its divisors is an integer number (233248758).

Almost surely, 2^621996686 is an apocalyptic number.

621996686 is a deficient number, since it is larger than the sum of its proper divisors (310998346).

621996686 is a wasteful number, since it uses less digits than its factorization.

621996686 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 310998345.

The product of its digits is 1679616, while the sum is 53.

The square root of 621996686 is about 24939.8613869444. The cubic root of 621996686 is about 853.6162819358.

The spelling of 621996686 in words is "six hundred twenty-one million, nine hundred ninety-six thousand, six hundred eighty-six".