21752638242 has 16 divisors (see below), whose sum is σ = 43507184832. Its totient is φ = 7250561360.

The previous prime is 21752638241. The next prime is 21752638267. The reversal of 21752638242 is 24283625712.

It is a junction number, because it is equal to n+sod(n) for n = 21752638194 and 21752638203.

It is not an unprimeable number, because it can be changed into a prime (21752638241) 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, 99763 + ... + 231209.

It is an arithmetic number, because the mean of its divisors is an integer number (2719199052).

Almost surely, 2^21752638242 is an apocalyptic number.

21752638242 is an abundant number, since it is smaller than the sum of its proper divisors (21754546590).

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

21752638242 is a wasteful number, since it uses less digits than its factorization.

21752638242 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 159033.

The product of its digits is 322560, while the sum is 42.

The spelling of 21752638242 in words is "twenty-one billion, seven hundred fifty-two million, six hundred thirty-eight thousand, two hundred forty-two".