21549148600 has 48 divisors (see below), whose sum is σ = 57259170000. Its totient is φ = 7388279040.

The previous prime is 21549148597. The next prime is 21549148601. The reversal of 21549148600 is 684194512.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21549148601) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 7694725 + ... + 7697524.

It is an arithmetic number, because the mean of its divisors is an integer number (1192899375).

Almost surely, 2^21549148600 is an apocalyptic number.

21549148600 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21549148600 is an abundant number, since it is smaller than the sum of its proper divisors (35710021400).

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

21549148600 is a wasteful number, since it uses less digits than its factorization.

21549148600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15392272 (or 15392263 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 40.

The spelling of 21549148600 in words is "twenty-one billion, five hundred forty-nine million, one hundred forty-eight thousand, six hundred".