21051441554 has 32 divisors (see below), whose sum is σ = 38002487040. Its totient is φ = 8617334400.

The previous prime is 21051441527. The next prime is 21051441577. The reversal of 21051441554 is 45514415012.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 21051441554.

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, 885914 + ... + 909365.

It is an arithmetic number, because the mean of its divisors is an integer number (1187577720).

Almost surely, 2^21051441554 is an apocalyptic number.

21051441554 is a deficient number, since it is larger than the sum of its proper divisors (16951045486).

21051441554 is a wasteful number, since it uses less digits than its factorization.

21051441554 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1795346.

The product of its (nonzero) digits is 16000, while the sum is 32.

Adding to 21051441554 its reverse (45514415012), we get a palindrome (66565856566).

The spelling of 21051441554 in words is "twenty-one billion, fifty-one million, four hundred forty-one thousand, five hundred fifty-four".