21140912947 has 24 divisors (see below), whose sum is σ = 27167823360. Its totient is φ = 16264881360.

The previous prime is 21140912929. The next prime is 21140912953. The reversal of 21140912947 is 74921904112.

It is a de Polignac number, because none of the positive numbers 2^k-21140912947 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21140912147) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 205663 + ... + 290824.

It is an arithmetic number, because the mean of its divisors is an integer number (1131992640).

Almost surely, 2^21140912947 is an apocalyptic number.

21140912947 is a deficient number, since it is larger than the sum of its proper divisors (6026910413).

21140912947 is a wasteful number, since it uses less digits than its factorization.

21140912947 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 496591 (or 496584 counting only the distinct ones).

The product of its (nonzero) digits is 36288, while the sum is 40.

The spelling of 21140912947 in words is "twenty-one billion, one hundred forty million, nine hundred twelve thousand, nine hundred forty-seven".