621016257709 has 4 divisors (see below), whose sum is σ = 621238926780. Its totient is φ = 620793588640.

The previous prime is 621016257707. The next prime is 621016257731. The reversal of 621016257709 is 907752610126.

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

It can be written as a sum of positive squares in 2 ways, for example, as 209040984100 + 411975273609 = 457210^2 + 641853^2 .

It is a cyclic number.

It is not a de Polignac number, because 621016257709 - 2¹ = 621016257707 is a prime.

It is a super-2 number, since 2×621016257709² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (621016257707) 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, 111330352 + ... + 111335929.

It is an arithmetic number, because the mean of its divisors is an integer number (155309731695).

Almost surely, 2^621016257709 is an apocalyptic number.

It is an amenable number.

621016257709 is a deficient number, since it is larger than the sum of its proper divisors (222669071).

621016257709 is a wasteful number, since it uses less digits than its factorization.

621016257709 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 222669070.

The product of its (nonzero) digits is 317520, while the sum is 46.

The spelling of 621016257709 in words is "six hundred twenty-one billion, sixteen million, two hundred fifty-seven thousand, seven hundred nine".