21719990340 has 72 divisors (see below), whose sum is σ = 66034288320. Its totient is φ = 5778782784.

The previous prime is 21719990339. The next prime is 21719990363. The reversal of 21719990340 is 4309991712.

21719990340 is a `hidden beast` number, since 217 + 1 + 9 + 9 + 90 + 340 = 666.

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 58414 + ... + 216453.

Almost surely, 2^21719990340 is an apocalyptic number.

21719990340 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21719990340 is an abundant number, since it is smaller than the sum of its proper divisors (44314297980).

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

21719990340 is a wasteful number, since it uses less digits than its factorization.

21719990340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 275321 (or 275316 counting only the distinct ones).

The product of its (nonzero) digits is 122472, while the sum is 45.

The spelling of 21719990340 in words is "twenty-one billion, seven hundred nineteen million, nine hundred ninety thousand, three hundred forty".