21798751740 has 48 divisors (see below), whose sum is σ = 63005429760. Its totient is φ = 5625483840.

The previous prime is 21798751673. The next prime is 21798751747. The reversal of 21798751740 is 4715789712.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21798751747) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 5858020 + ... + 5861739.

It is an arithmetic number, because the mean of its divisors is an integer number (1312613120).

Almost surely, 2^21798751740 is an apocalyptic number.

21798751740 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21798751740 is an abundant number, since it is smaller than the sum of its proper divisors (41206678020).

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

21798751740 is a wasteful number, since it uses less digits than its factorization.

21798751740 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11719802 (or 11719800 counting only the distinct ones).

The product of its (nonzero) digits is 987840, while the sum is 51.

The spelling of 21798751740 in words is "twenty-one billion, seven hundred ninety-eight million, seven hundred fifty-one thousand, seven hundred forty".