21430051242 has 32 divisors (see below), whose sum is σ = 43238448000. Its totient is φ = 7080564288.

The previous prime is 21430051231. The next prime is 21430051243. The reversal of 21430051242 is 24215003412.

It is not an unprimeable number, because it can be changed into a prime (21430051243) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 284259 + ... + 351657.

It is an arithmetic number, because the mean of its divisors is an integer number (1351201500).

Almost surely, 2^21430051242 is an apocalyptic number.

21430051242 is an abundant number, since it is smaller than the sum of its proper divisors (21808396758).

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

21430051242 is a wasteful number, since it uses less digits than its factorization.

21430051242 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67870.

The product of its (nonzero) digits is 1920, while the sum is 24.

Adding to 21430051242 its reverse (24215003412), we get a palindrome (45645054654).

The spelling of 21430051242 in words is "twenty-one billion, four hundred thirty million, fifty-one thousand, two hundred forty-two".