21115742140 has 24 divisors (see below), whose sum is σ = 44347317840. Its totient is φ = 8445485568.

The previous prime is 21115742129. The next prime is 21115742203. The reversal of 21115742140 is 4124751112.

It is a super-2 number, since 2×21115742140² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21115742099 and 21115742108.

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 7 ways as a sum of consecutive naturals, for example, 190764 + ... + 280396.

It is an arithmetic number, because the mean of its divisors is an integer number (1847804910).

Almost surely, 2^21115742140 is an apocalyptic number.

21115742140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21115742140 is an abundant number, since it is smaller than the sum of its proper divisors (23231575700).

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

21115742140 is a wasteful number, since it uses less digits than its factorization.

21115742140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 101421 (or 101419 counting only the distinct ones).

The product of its (nonzero) digits is 2240, while the sum is 28.

The spelling of 21115742140 in words is "twenty-one billion, one hundred fifteen million, seven hundred forty-two thousand, one hundred forty".