21168158801 has 2 divisors, whose sum is σ = 21168158802. Its totient is φ = 21168158800.

The previous prime is 21168158773. The next prime is 21168158833. The reversal of 21168158801 is 10885186112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20757893776 + 410265025 = 144076^2 + 20255^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21168158801 is a prime.

It is not a weakly prime, because it can be changed into another prime (21168158101) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10584079400 + 10584079401.

It is an arithmetic number, because the mean of its divisors is an integer number (10584079401).

Almost surely, 2^21168158801 is an apocalyptic number.

It is an amenable number.

21168158801 is a deficient number, since it is larger than the sum of its proper divisors (1).

21168158801 is an equidigital number, since it uses as much as digits as its factorization.

21168158801 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 30720, while the sum is 41.

The spelling of 21168158801 in words is "twenty-one billion, one hundred sixty-eight million, one hundred fifty-eight thousand, eight hundred one".