21043042140 has 48 divisors (see below), whose sum is σ = 59492579328. Its totient is φ = 5556995904.

The previous prime is 21043042117. The next prime is 21043042177. The reversal of 21043042140 is 4124034012.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1696332 + ... + 1708691.

It is an arithmetic number, because the mean of its divisors is an integer number (1239428736).

Almost surely, 2^21043042140 is an apocalyptic number.

21043042140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21043042140 is an abundant number, since it is smaller than the sum of its proper divisors (38449537188).

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

21043042140 is a wasteful number, since it uses less digits than its factorization.

21043042140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3405138 (or 3405136 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 21.

Adding to 21043042140 its reverse (4124034012), we get a palindrome (25167076152).

The spelling of 21043042140 in words is "twenty-one billion, forty-three million, forty-two thousand, one hundred forty".