21154992480 has 192 divisors, whose sum is σ = 74429046720. Its totient is φ = 5611880448.

The previous prime is 21154992433. The next prime is 21154992487. The reversal of 21154992480 is 8429945112.

It is a happy number.

21154992480 is a `hidden beast` number, since 2 + 1 + 1 + 549 + 9 + 24 + 80 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21154992487) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 821074 + ... + 846446.

It is an arithmetic number, because the mean of its divisors is an integer number (387651285).

Almost surely, 2^21154992480 is an apocalyptic number.

21154992480 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 21154992480, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37214523360).

21154992480 is an abundant number, since it is smaller than the sum of its proper divisors (53274054240).

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

21154992480 is a wasteful number, since it uses less digits than its factorization.

21154992480 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25590 (or 25576 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 45.

The spelling of 21154992480 in words is "twenty-one billion, one hundred fifty-four million, nine hundred ninety-two thousand, four hundred eighty".