21340859490 has 24 divisors (see below), whose sum is σ = 55486234908. Its totient is φ = 5690895840.

The previous prime is 21340859483. The next prime is 21340859549. The reversal of 21340859490 is 9495804312.

21340859490 is a `hidden beast` number, since 2 + 13 + 40 + 8 + 594 + 9 + 0 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 21337321329 + 3538161 = 146073^2 + 1881^2 .

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 118560241 + ... + 118560420.

Almost surely, 2^21340859490 is an apocalyptic number.

21340859490 is an abundant number, since it is smaller than the sum of its proper divisors (34145375418).

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

21340859490 is a wasteful number, since it uses less digits than its factorization.

21340859490 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 237120674 (or 237120671 counting only the distinct ones).

The product of its (nonzero) digits is 311040, while the sum is 45.

The spelling of 21340859490 in words is "twenty-one billion, three hundred forty million, eight hundred fifty-nine thousand, four hundred ninety".