21122002254 has 16 divisors (see below), whose sum is σ = 42245481600. Its totient is φ = 7040421240.

The previous prime is 21122002201. The next prime is 21122002259. The reversal of 21122002254 is 45220022112.

It is a super-2 number, since 2×21122002254² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21122002254.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21122002259) 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 7 ways as a sum of consecutive naturals, for example, 232197 + ... + 310095.

It is an arithmetic number, because the mean of its divisors is an integer number (2640342600).

Almost surely, 2^21122002254 is an apocalyptic number.

21122002254 is an abundant number, since it is smaller than the sum of its proper divisors (21123479346).

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

21122002254 is a wasteful number, since it uses less digits than its factorization.

21122002254 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 123095.

The product of its (nonzero) digits is 640, while the sum is 21.

Adding to 21122002254 its reverse (45220022112), we get a palindrome (66342024366).

The spelling of 21122002254 in words is "twenty-one billion, one hundred twenty-two million, two thousand, two hundred fifty-four".