21972951000 has 1280 divisors, whose sum is σ = 103506923520. Its totient is φ = 4199040000.

The previous prime is 21972950999. The next prime is 21972951037. The reversal of 21972951000 is 15927912.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 319 ways as a sum of consecutive naturals, for example, 81080865 + ... + 81081135.

It is an arithmetic number, because the mean of its divisors is an integer number (80864784).

Almost surely, 2^21972951000 is an apocalyptic number.

21972951000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21972951000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (51753461760).

21972951000 is an abundant number, since it is smaller than the sum of its proper divisors (81533972520).

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

21972951000 is a wasteful number, since it uses less digits than its factorization.

21972951000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 335 (or 312 counting only the distinct ones).

The product of its (nonzero) digits is 11340, while the sum is 36.

The spelling of 21972951000 in words is "twenty-one billion, nine hundred seventy-two million, nine hundred fifty-one thousand".