21242505254 has 16 divisors (see below), whose sum is σ = 31930080000. Its totient is φ = 10599167304.

The previous prime is 21242505241. The next prime is 21242505289. The reversal of 21242505254 is 45250524212.

It is a self number, because there is not a number n which added to its sum of digits gives 21242505254.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2466047 + ... + 2474645.

It is an arithmetic number, because the mean of its divisors is an integer number (1995630000).

Almost surely, 2^21242505254 is an apocalyptic number.

21242505254 is a deficient number, since it is larger than the sum of its proper divisors (10687574746).

21242505254 is a wasteful number, since it uses less digits than its factorization.

21242505254 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11027.

The product of its (nonzero) digits is 32000, while the sum is 32.

The spelling of 21242505254 in words is "twenty-one billion, two hundred forty-two million, five hundred five thousand, two hundred fifty-four".