21254212554 has 64 divisors (see below), whose sum is σ = 47456962560. Its totient is φ = 6314742720.

The previous prime is 21254212537. The next prime is 21254212561. The reversal of 21254212554 is 45521245212.

It is a super-2 number, since 2×21254212554² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 93499 + ... + 226385.

It is an arithmetic number, because the mean of its divisors is an integer number (741515040).

Almost surely, 2^21254212554 is an apocalyptic number.

21254212554 is an abundant number, since it is smaller than the sum of its proper divisors (26202750006).

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

21254212554 is a wasteful number, since it uses less digits than its factorization.

21254212554 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 132995.

The product of its digits is 32000, while the sum is 33.

Adding to 21254212554 its reverse (45521245212), we get a palindrome (66775457766).

The spelling of 21254212554 in words is "twenty-one billion, two hundred fifty-four million, two hundred twelve thousand, five hundred fifty-four".