21481254420 has 24 divisors (see below), whose sum is σ = 60147512544. Its totient is φ = 5728334496.

The previous prime is 21481254397. The next prime is 21481254433. The reversal of 21481254420 is 2445218412.

It is a super-2 number, since 2×21481254420² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 179010394 + ... + 179010513.

It is an arithmetic number, because the mean of its divisors is an integer number (2506146356).

Almost surely, 2^21481254420 is an apocalyptic number.

21481254420 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21481254420 is an abundant number, since it is smaller than the sum of its proper divisors (38666258124).

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

21481254420 is a wasteful number, since it uses less digits than its factorization.

21481254420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 358020919 (or 358020917 counting only the distinct ones).

The product of its (nonzero) digits is 20480, while the sum is 33.

The spelling of 21481254420 in words is "twenty-one billion, four hundred eighty-one million, two hundred fifty-four thousand, four hundred twenty".