21912425640 has 1152 divisors, whose sum is σ = 95068339200. Its totient is φ = 4467778560.

The previous prime is 21912425597. The next prime is 21912425641. The reversal of 21912425640 is 4652421912.

It is a happy number.

21912425640 is a `hidden beast` number, since 2 + 1 + 9 + 1 + 2 + 4 + 2 + 5 + 640 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 21912425595 and 21912425604.

It is not an unprimeable number, because it can be changed into a prime (21912425641) by changing a digit.

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 287 ways as a sum of consecutive naturals, for example, 592227702 + ... + 592227738.

It is an arithmetic number, because the mean of its divisors is an integer number (82524600).

Almost surely, 2^21912425640 is an apocalyptic number.

21912425640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21912425640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (47534169600).

21912425640 is an abundant number, since it is smaller than the sum of its proper divisors (73155913560).

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

21912425640 is a wasteful number, since it uses less digits than its factorization.

21912425640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 140 (or 104 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 36.

The spelling of 21912425640 in words is "twenty-one billion, nine hundred twelve million, four hundred twenty-five thousand, six hundred forty".