21249089280 has 216 divisors, whose sum is σ = 77389887120. Its totient is φ = 5368135680.

The previous prime is 21249089269. The next prime is 21249089287. The reversal of 21249089280 is 8298094212.

It is a happy number.

21249089280 is a `hidden beast` number, since 2 + 1 + 2 + 490 + 89 + 2 + 80 = 666.

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

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 (21249089287) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 170340 + ... + 267420.

Almost surely, 2^21249089280 is an apocalyptic number.

21249089280 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 21249089280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38694943560).

21249089280 is an abundant number, since it is smaller than the sum of its proper divisors (56140797840).

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

21249089280 is a wasteful number, since it uses less digits than its factorization.

21249089280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 97127 (or 97110 counting only the distinct ones).

The product of its (nonzero) digits is 165888, while the sum is 45.

The spelling of 21249089280 in words is "twenty-one billion, two hundred forty-nine million, eighty-nine thousand, two hundred eighty".