21810872160 has 2304 divisors, whose sum is σ = 111694464000. Its totient is φ = 3901685760.

The previous prime is 21810872113. The next prime is 21810872197. The reversal of 21810872160 is 6127801812.

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 polite number, since it can be written in 383 ways as a sum of consecutive naturals, for example, 752099026 + ... + 752099054.

It is an arithmetic number, because the mean of its divisors is an integer number (48478500).

Almost surely, 2^21810872160 is an apocalyptic number.

21810872160 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 21810872160, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (55847232000).

21810872160 is an abundant number, since it is smaller than the sum of its proper divisors (89883591840).

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

21810872160 is a wasteful number, since it uses less digits than its factorization.

21810872160 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 114 (or 93 counting only the distinct ones).

The product of its (nonzero) digits is 10752, while the sum is 36.

The spelling of 21810872160 in words is "twenty-one billion, eight hundred ten million, eight hundred seventy-two thousand, one hundred sixty".