21407789292 has 24 divisors (see below), whose sum is σ = 50165899056. Its totient is φ = 7105302528.

The previous prime is 21407789267. The next prime is 21407789297. The reversal of 21407789292 is 29298770412.

It is a super-2 number, since 2×21407789292² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21407789297) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3825493 + ... + 3831084.

It is an arithmetic number, because the mean of its divisors is an integer number (2090245794).

Almost surely, 2^21407789292 is an apocalyptic number.

It is an amenable number.

21407789292 is an abundant number, since it is smaller than the sum of its proper divisors (28758109764).

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

21407789292 is a wasteful number, since it uses less digits than its factorization.

21407789292 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7656817 (or 7656815 counting only the distinct ones).

The product of its (nonzero) digits is 1016064, while the sum is 51.

The spelling of 21407789292 in words is "twenty-one billion, four hundred seven million, seven hundred eighty-nine thousand, two hundred ninety-two".