21122500542 has 32 divisors (see below), whose sum is σ = 49630492800. Its totient is φ = 5908391520.

The previous prime is 21122500447. The next prime is 21122500571. The reversal of 21122500542 is 24500522112.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12308292 + ... + 12310007.

It is an arithmetic number, because the mean of its divisors is an integer number (1550952900).

Almost surely, 2^21122500542 is an apocalyptic number.

21122500542 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

21122500542 is an abundant number, since it is smaller than the sum of its proper divisors (28507992258).

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

21122500542 is a wasteful number, since it uses less digits than its factorization.

21122500542 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24618328.

The product of its (nonzero) digits is 1600, while the sum is 24.

The spelling of 21122500542 in words is "twenty-one billion, one hundred twenty-two million, five hundred thousand, five hundred forty-two".