21150442440 has 64 divisors (see below), whose sum is σ = 70501478400. Its totient is φ = 5640117696.

The previous prime is 21150442399. The next prime is 21150442457. The reversal of 21150442440 is 4424405112.

21150442440 is a `hidden beast` number, since 211 + 5 + 0 + 4 + 4 + 2 + 440 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9790792 + ... + 9792951.

It is an arithmetic number, because the mean of its divisors is an integer number (1101585600).

Almost surely, 2^21150442440 is an apocalyptic number.

21150442440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21150442440 is an abundant number, since it is smaller than the sum of its proper divisors (49351035960).

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

21150442440 is a wasteful number, since it uses less digits than its factorization.

21150442440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19583763 (or 19583753 counting only the distinct ones).

The product of its (nonzero) digits is 5120, while the sum is 27.

Adding to 21150442440 its reverse (4424405112), we get a palindrome (25574847552).

The spelling of 21150442440 in words is "twenty-one billion, one hundred fifty million, four hundred forty-two thousand, four hundred forty".