21112501305 has 16 divisors (see below), whose sum is σ = 38605716864. Its totient is φ = 9651429120.

The previous prime is 21112501279. The next prime is 21112501307. The reversal of 21112501305 is 50310521112.

It is not a de Polignac number, because 21112501305 - 2⁵ = 21112501273 is a prime.

It is a super-2 number, since 2×21112501305² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is not an unprimeable number, because it can be changed into a prime (21112501307) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 100535616 + ... + 100535825.

It is an arithmetic number, because the mean of its divisors is an integer number (2412857304).

Almost surely, 2^21112501305 is an apocalyptic number.

It is an amenable number.

21112501305 is a deficient number, since it is larger than the sum of its proper divisors (17493215559).

21112501305 is a wasteful number, since it uses less digits than its factorization.

21112501305 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 201071456.

The product of its (nonzero) digits is 300, while the sum is 21.

The spelling of 21112501305 in words is "twenty-one billion, one hundred twelve million, five hundred one thousand, three hundred five".