2856621621 has 16 divisors (see below), whose sum is σ = 4360922624. Its totient is φ = 1629364464.

The previous prime is 2856621617. The next prime is 2856621629. The reversal of 2856621621 is 1261266582.

It is not a de Polignac number, because 2856621621 - 2² = 2856621617 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2856621621.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2856621629) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 112855 + ... + 135828.

It is an arithmetic number, because the mean of its divisors is an integer number (272557664).

Almost surely, 2^2856621621 is an apocalyptic number.

2856621621 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

2856621621 is a deficient number, since it is larger than the sum of its proper divisors (1504301003).

2856621621 is a wasteful number, since it uses less digits than its factorization.

2856621621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 249240.

The product of its digits is 69120, while the sum is 39.

The square root of 2856621621 is about 53447.3724424316. The cubic root of 2856621621 is about 1418.8971170878.

The spelling of 2856621621 in words is "two billion, eight hundred fifty-six million, six hundred twenty-one thousand, six hundred twenty-one".