21748978490 has 32 divisors (see below), whose sum is σ = 40270970880. Its totient is φ = 8451856000.

The previous prime is 21748978487. The next prime is 21748978507. The reversal of 21748978490 is 9487984712.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12986 + ... + 208965.

It is an arithmetic number, because the mean of its divisors is an integer number (1258467840).

Almost surely, 2^21748978490 is an apocalyptic number.

21748978490 is a deficient number, since it is larger than the sum of its proper divisors (18521992390).

21748978490 is a wasteful number, since it uses less digits than its factorization.

21748978490 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 222238.

The product of its (nonzero) digits is 8128512, while the sum is 59.

The spelling of 21748978490 in words is "twenty-one billion, seven hundred forty-eight million, nine hundred seventy-eight thousand, four hundred ninety".