21427374353840 has 1440 divisors, whose sum is σ = 68535665490240. Its totient is φ = 6185175220224.

The previous prime is 21427374353821. The next prime is 21427374353843. The reversal of 21427374353840 is 4835347372412.

It is not an unprimeable number, because it can be changed into a prime (21427374353843) by changing a digit.

It is a polite number, since it can be written in 287 ways as a sum of consecutive naturals, for example, 55083224366 + ... + 55083224754.

It is an arithmetic number, because the mean of its divisors is an integer number (47594212146).

Almost surely, 2^{21427374353840} is an apocalyptic number.

21427374353840 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 21427374353840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34267832745120).

21427374353840 is an abundant number, since it is smaller than the sum of its proper divisors (47108291136400).

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

21427374353840 is a wasteful number, since it uses less digits than its factorization.

21427374353840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 599 (or 573 counting only the distinct ones).

The product of its (nonzero) digits is 13547520, while the sum is 53.

The spelling of 21427374353840 in words is "twenty-one trillion, four hundred twenty-seven billion, three hundred seventy-four million, three hundred fifty-three thousand, eight hundred forty".