21406770620 has 24 divisors (see below), whose sum is σ = 45523262400. Its totient is φ = 8454318912.

The previous prime is 21406770559. The next prime is 21406770683. The reversal of 21406770620 is 2607760412.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6772715 + ... + 6775874.

It is an arithmetic number, because the mean of its divisors is an integer number (1896802600).

Almost surely, 2^21406770620 is an apocalyptic number.

21406770620 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21406770620 is an abundant number, since it is smaller than the sum of its proper divisors (24116491780).

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

21406770620 is a wasteful number, since it uses less digits than its factorization.

21406770620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13548677 (or 13548675 counting only the distinct ones).

The product of its (nonzero) digits is 28224, while the sum is 35.

The spelling of 21406770620 in words is "twenty-one billion, four hundred six million, seven hundred seventy thousand, six hundred twenty".