21440500254 has 20 divisors (see below), whose sum is σ = 48042602784. Its totient is φ = 7146833364.

The previous prime is 21440500253. The next prime is 21440500337. The reversal of 21440500254 is 45200504412.

21440500254 is a `hidden beast` number, since 2 + 1 + 4 + 405 + 0 + 0 + 254 = 666.

It is a super-2 number, since 2×21440500254² (a number of 21 digits) contains 22 as substring.

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

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21440500253) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 66174222 + ... + 66174545.

Almost surely, 2^21440500254 is an apocalyptic number.

21440500254 is an abundant number, since it is smaller than the sum of its proper divisors (26602102530).

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

21440500254 is a wasteful number, since it uses less digits than its factorization.

21440500254 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 132348781 (or 132348772 counting only the distinct ones).

The product of its (nonzero) digits is 6400, while the sum is 27.

The spelling of 21440500254 in words is "twenty-one billion, four hundred forty million, five hundred thousand, two hundred fifty-four".