21620157039541 has 2 divisors, whose sum is σ = 21620157039542. Its totient is φ = 21620157039540.

The previous prime is 21620157039521. The next prime is 21620157039563. The reversal of 21620157039541 is 14593075102612.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17817930034641 + 3802227004900 = 4221129^2 + 1949930^2 .

It is a cyclic number.

It is not a de Polignac number, because 21620157039541 - 2¹³ = 21620157031349 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21620157039491 and 21620157039500.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21620157039521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10810078519770 + 10810078519771.

It is an arithmetic number, because the mean of its divisors is an integer number (10810078519771).

Almost surely, 2^{21620157039541} is an apocalyptic number.

It is an amenable number.

21620157039541 is a deficient number, since it is larger than the sum of its proper divisors (1).

21620157039541 is an equidigital number, since it uses as much as digits as its factorization.

21620157039541 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 453600, while the sum is 46.

The spelling of 21620157039541 in words is "twenty-one trillion, six hundred twenty billion, one hundred fifty-seven million, thirty-nine thousand, five hundred forty-one".