621981051 has 4 divisors (see below), whose sum is σ = 829308072. Its totient is φ = 414654032.

The previous prime is 621981037. The next prime is 621981089. The reversal of 621981051 is 150189126.

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

It is a cyclic number.

It is not a de Polignac number, because 621981051 - 2⁹ = 621980539 is a prime.

It is not an unprimeable number, because it can be changed into a prime (621981011) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 103663506 + ... + 103663511.

It is an arithmetic number, because the mean of its divisors is an integer number (207327018).

Almost surely, 2^621981051 is an apocalyptic number.

621981051 is a deficient number, since it is larger than the sum of its proper divisors (207327021).

621981051 is a wasteful number, since it uses less digits than its factorization.

621981051 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 207327020.

The product of its (nonzero) digits is 4320, while the sum is 33.

The square root of 621981051 is about 24939.5479309469. The cubic root of 621981051 is about 853.6091294848.

The spelling of 621981051 in words is "six hundred twenty-one million, nine hundred eighty-one thousand, fifty-one".