21719996550 has 288 divisors, whose sum is σ = 69148145664. Its totient is φ = 4783104000.

The previous prime is 21719996531. The next prime is 21719996563. The reversal of 21719996550 is 5569991712.

It is a Smith number, since the sum of its digits (54) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 33884230 + ... + 33884870.

It is an arithmetic number, because the mean of its divisors is an integer number (240097728).

Almost surely, 2^21719996550 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21719996550, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34574072832).

21719996550 is an abundant number, since it is smaller than the sum of its proper divisors (47428149114).

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

21719996550 is a wasteful number, since it uses less digits than its factorization.

21719996550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1044 (or 1036 counting only the distinct ones).

The product of its (nonzero) digits is 1530900, while the sum is 54.

The spelling of 21719996550 in words is "twenty-one billion, seven hundred nineteen million, nine hundred ninety-six thousand, five hundred fifty".