21952491408 has 240 divisors, whose sum is σ = 66866095296. Its totient is φ = 6696345600.

The previous prime is 21952491389. The next prime is 21952491409. The reversal of 21952491408 is 80419425912.

It is a happy number.

21952491408 is a `hidden beast` number, since 219 + 5 + 24 + 9 + 1 + 408 = 666.

It is not an unprimeable number, because it can be changed into a prime (21952491409) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 36526308 + ... + 36526908.

Almost surely, 2^21952491408 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21952491408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33433047648).

21952491408 is an abundant number, since it is smaller than the sum of its proper divisors (44913603888).

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

21952491408 is a wasteful number, since it uses less digits than its factorization.

21952491408 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1022 (or 1013 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 45.

The spelling of 21952491408 in words is "twenty-one billion, nine hundred fifty-two million, four hundred ninety-one thousand, four hundred eight".