21170501153 has 2 divisors, whose sum is σ = 21170501154. Its totient is φ = 21170501152.

The previous prime is 21170501029. The next prime is 21170501171. The reversal of 21170501153 is 35110507112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13126743184 + 8043757969 = 114572^2 + 89687^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21170501153 is a prime.

It is not a weakly prime, because it can be changed into another prime (21170501173) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10585250576 + 10585250577.

It is an arithmetic number, because the mean of its divisors is an integer number (10585250577).

Almost surely, 2^21170501153 is an apocalyptic number.

It is an amenable number.

21170501153 is a deficient number, since it is larger than the sum of its proper divisors (1).

21170501153 is an equidigital number, since it uses as much as digits as its factorization.

21170501153 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1050, while the sum is 26.

The spelling of 21170501153 in words is "twenty-one billion, one hundred seventy million, five hundred one thousand, one hundred fifty-three".