21101566151 has 4 divisors (see below), whose sum is σ = 21107528904. Its totient is φ = 21095603400.

The previous prime is 21101566141. The next prime is 21101566169. The reversal of 21101566151 is 15166510112.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21101566151 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21101566141) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2976065 + ... + 2983146.

It is an arithmetic number, because the mean of its divisors is an integer number (5276882226).

Almost surely, 2^21101566151 is an apocalyptic number.

21101566151 is a deficient number, since it is larger than the sum of its proper divisors (5962753).

21101566151 is an equidigital number, since it uses as much as digits as its factorization.

21101566151 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5962752.

The product of its (nonzero) digits is 1800, while the sum is 29.

The spelling of 21101566151 in words is "twenty-one billion, one hundred one million, five hundred sixty-six thousand, one hundred fifty-one".