2652021221581 has 2 divisors, whose sum is σ = 2652021221582. Its totient is φ = 2652021221580.

The previous prime is 2652021221561. The next prime is 2652021221659. The reversal of 2652021221581 is 1851221202562.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2534686884900 + 117334336681 = 1592070^2 + 342541^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2652021221581 is a prime.

It is a super-2 number, since 2×2652021221581² (a number of 26 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 2652021221581.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2652021221561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1326010610790 + 1326010610791.

It is an arithmetic number, because the mean of its divisors is an integer number (1326010610791).

Almost surely, 2^{2652021221581} is an apocalyptic number.

It is an amenable number.

2652021221581 is a deficient number, since it is larger than the sum of its proper divisors (1).

2652021221581 is an equidigital number, since it uses as much as digits as its factorization.

2652021221581 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 38400, while the sum is 37.

The spelling of 2652021221581 in words is "two trillion, six hundred fifty-two billion, twenty-one million, two hundred twenty-one thousand, five hundred eighty-one".