21953848739 has 16 divisors (see below), whose sum is σ = 24232732416. Its totient is φ = 19797888000.

The previous prime is 21953848723. The next prime is 21953848759. The reversal of 21953848739 is 93784835912.

It is a cyclic number.

It is not a de Polignac number, because 21953848739 - 2⁴ = 21953848723 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21953848759) 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, 153002 + ... + 259455.

It is an arithmetic number, because the mean of its divisors is an integer number (1514545776).

Almost surely, 2^21953848739 is an apocalyptic number.

21953848739 is a deficient number, since it is larger than the sum of its proper divisors (2278883677).

21953848739 is a wasteful number, since it uses less digits than its factorization.

21953848739 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 412606.

The product of its digits is 13063680, while the sum is 59.

The spelling of 21953848739 in words is "twenty-one billion, nine hundred fifty-three million, eight hundred forty-eight thousand, seven hundred thirty-nine".