21731734506 has 16 divisors (see below), whose sum is σ = 45353185344. Its totient is φ = 6928958784.

The previous prime is 21731734501. The next prime is 21731734543. The reversal of 21731734506 is 60543713712.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21731734501) 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, 78738031 + ... + 78738306.

It is an arithmetic number, because the mean of its divisors is an integer number (2834574084).

Almost surely, 2^21731734506 is an apocalyptic number.

21731734506 is an abundant number, since it is smaller than the sum of its proper divisors (23621450838).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21731734506 is a wasteful number, since it uses less digits than its factorization.

21731734506 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 157476365.

The product of its (nonzero) digits is 105840, while the sum is 39.

The spelling of 21731734506 in words is "twenty-one billion, seven hundred thirty-one million, seven hundred thirty-four thousand, five hundred six".