21386247120 has 240 divisors, whose sum is σ = 82577214720. Its totient is φ = 4858822656.

The previous prime is 21386247119. The next prime is 21386247137. The reversal of 21386247120 is 2174268312.

It is a happy number.

21386247120 is a `hidden beast` number, since 2 + 1 + 3 + 8 + 624 + 7 + 1 + 20 = 666.

It is a tau number, because it is divible by the number of its divisors (240).

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 pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 828976 + ... + 854384.

It is an arithmetic number, because the mean of its divisors is an integer number (344071728).

Almost surely, 2^21386247120 is an apocalyptic number.

21386247120 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 21386247120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41288607360).

21386247120 is an abundant number, since it is smaller than the sum of its proper divisors (61190967600).

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

21386247120 is a wasteful number, since it uses less digits than its factorization.

21386247120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25602 (or 25593 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 36.

The spelling of 21386247120 in words is "twenty-one billion, three hundred eighty-six million, two hundred forty-seven thousand, one hundred twenty".