21210677240 has 16 divisors (see below), whose sum is σ = 47724023880. Its totient is φ = 8484270880.

The previous prime is 21210677233. The next prime is 21210677273. The reversal of 21210677240 is 4277601212.

It is a junction number, because it is equal to n+sod(n) for n = 21210677197 and 21210677206.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 265133426 + ... + 265133505.

Almost surely, 2^21210677240 is an apocalyptic number.

21210677240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21210677240 is an abundant number, since it is smaller than the sum of its proper divisors (26513346640).

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

21210677240 is a wasteful number, since it uses less digits than its factorization.

21210677240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 530266942 (or 530266938 counting only the distinct ones).

The product of its (nonzero) digits is 9408, while the sum is 32.

The spelling of 21210677240 in words is "twenty-one billion, two hundred ten million, six hundred seventy-seven thousand, two hundred forty".