21570525337 has 2 divisors, whose sum is σ = 21570525338. Its totient is φ = 21570525336.

The previous prime is 21570525329. The next prime is 21570525341. The reversal of 21570525337 is 73352507512.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21569034496 + 1490841 = 146864^2 + 1221^2 .

It is a cyclic number.

It is not a de Polignac number, because 21570525337 - 2³ = 21570525329 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21570525337.

It is not a weakly prime, because it can be changed into another prime (21570525037) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10785262668 + 10785262669.

It is an arithmetic number, because the mean of its divisors is an integer number (10785262669).

Almost surely, 2^21570525337 is an apocalyptic number.

It is an amenable number.

21570525337 is a deficient number, since it is larger than the sum of its proper divisors (1).

21570525337 is an equidigital number, since it uses as much as digits as its factorization.

21570525337 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 220500, while the sum is 40.

The spelling of 21570525337 in words is "twenty-one billion, five hundred seventy million, five hundred twenty-five thousand, three hundred thirty-seven".