21917449026 has 96 divisors (see below), whose sum is σ = 52538840640. Its totient is φ = 6548169600.

The previous prime is 21917448991. The next prime is 21917449027. The reversal of 21917449026 is 62094471912.

21917449026 is a `hidden beast` number, since 2 + 1 + 91 + 74 + 490 + 2 + 6 = 666.

It is not an unprimeable number, because it can be changed into a prime (21917449027) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 4551396 + ... + 4556208.

It is an arithmetic number, because the mean of its divisors is an integer number (547279590).

Almost surely, 2^21917449026 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21917449026, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26269420320).

21917449026 is an abundant number, since it is smaller than the sum of its proper divisors (30621391614).

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

21917449026 is a wasteful number, since it uses less digits than its factorization.

21917449026 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5152 (or 5149 counting only the distinct ones).

The product of its (nonzero) digits is 217728, while the sum is 45.

The spelling of 21917449026 in words is "twenty-one billion, nine hundred seventeen million, four hundred forty-nine thousand, twenty-six".