2646651621 has 32 divisors (see below), whose sum is σ = 3718512000. Its totient is φ = 1672070400.

The previous prime is 2646651599. The next prime is 2646651649. The reversal of 2646651621 is 1261566462.

2646651621 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 2646651621 - 2²¹ = 2644554469 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2646651621.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2646651671) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2033671 + ... + 2034971.

It is an arithmetic number, because the mean of its divisors is an integer number (116203500).

Almost surely, 2^2646651621 is an apocalyptic number.

It is an amenable number.

2646651621 is a deficient number, since it is larger than the sum of its proper divisors (1071860379).

2646651621 is a wasteful number, since it uses less digits than its factorization.

2646651621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1749.

The product of its digits is 103680, while the sum is 39.

The square root of 2646651621 is about 51445.6180932837. The cubic root of 2646651621 is about 1383.2444178717.

It can be divided in two parts, 26466 and 51621, that added together give a palindrome (78087).

The spelling of 2646651621 in words is "two billion, six hundred forty-six million, six hundred fifty-one thousand, six hundred twenty-one".