2131455621 has 16 divisors (see below), whose sum is σ = 2872816128. Its totient is φ = 1405560000.

The previous prime is 2131455619. The next prime is 2131455649. The reversal of 2131455621 is 1265541312.

It is not a de Polignac number, because 2131455621 - 2¹ = 2131455619 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2131455661) 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, 391500 + ... + 396906.

It is an arithmetic number, because the mean of its divisors is an integer number (179551008).

Almost surely, 2^2131455621 is an apocalyptic number.

It is an amenable number.

2131455621 is a deficient number, since it is larger than the sum of its proper divisors (741360507).

2131455621 is a wasteful number, since it uses less digits than its factorization.

2131455621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6812.

The product of its digits is 7200, while the sum is 30.

The square root of 2131455621 is about 46167.6902281238. The cubic root of 2131455621 is about 1286.9413787492.

Adding to 2131455621 its reverse (1265541312), we get a palindrome (3396996933).

The spelling of 2131455621 in words is "two billion, one hundred thirty-one million, four hundred fifty-five thousand, six hundred twenty-one".