21956378234 has 16 divisors (see below), whose sum is σ = 37641734208. Its totient is φ = 9409319232.

The previous prime is 21956378233. The next prime is 21956378287. The reversal of 21956378234 is 43287365912.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21956378233) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 275369 + ... + 346035.

It is an arithmetic number, because the mean of its divisors is an integer number (2352608388).

Almost surely, 2^21956378234 is an apocalyptic number.

21956378234 is a deficient number, since it is larger than the sum of its proper divisors (15685355974).

21956378234 is a wasteful number, since it uses less digits than its factorization.

21956378234 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 92869.

The product of its digits is 2177280, while the sum is 50.

The spelling of 21956378234 in words is "twenty-one billion, nine hundred fifty-six million, three hundred seventy-eight thousand, two hundred thirty-four".