2521721679 has 16 divisors (see below), whose sum is σ = 3560854272. Its totient is φ = 1584050688.

The previous prime is 2521721677. The next prime is 2521721681. The reversal of 2521721679 is 9761271252.

It is an interprime number because it is at equal distance from previous prime (2521721677) and next prime (2521721681).

It is not a de Polignac number, because 2521721679 - 2¹ = 2521721677 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2521721679.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2521721677) 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, 268114 + ... + 277359.

It is an arithmetic number, because the mean of its divisors is an integer number (222553392).

Almost surely, 2^2521721679 is an apocalyptic number.

2521721679 is a deficient number, since it is larger than the sum of its proper divisors (1039132593).

2521721679 is a wasteful number, since it uses less digits than its factorization.

2521721679 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 545566.

The product of its digits is 105840, while the sum is 42.

The square root of 2521721679 is about 50216.7469973912. The cubic root of 2521721679 is about 1361.1282590564.

The spelling of 2521721679 in words is "two billion, five hundred twenty-one million, seven hundred twenty-one thousand, six hundred seventy-nine".