21122951850 has 1152 divisors, whose sum is σ = 83119680000. Its totient is φ = 3911846400.

The previous prime is 21122951849. The next prime is 21122951891. The reversal of 21122951850 is 5815922112.

21122951850 is a `hidden beast` number, since 2 + 112 + 29 + 518 + 5 + 0 = 666.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 575 ways as a sum of consecutive naturals, for example, 728377636 + ... + 728377664.

It is an arithmetic number, because the mean of its divisors is an integer number (72152500).

Almost surely, 2^21122951850 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21122951850, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41559840000).

21122951850 is an abundant number, since it is smaller than the sum of its proper divisors (61996728150).

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

21122951850 is a wasteful number, since it uses less digits than its factorization.

21122951850 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 106 (or 70 counting only the distinct ones).

The product of its (nonzero) digits is 14400, while the sum is 36.

The spelling of 21122951850 in words is "twenty-one billion, one hundred twenty-two million, nine hundred fifty-one thousand, eight hundred fifty".