21551054 has 16 divisors (see below), whose sum is σ = 38889600. Its totient is φ = 8749944.

The previous prime is 21551039. The next prime is 21551071. The reversal of 21551054 is 45015512.

It is a happy number.

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, 40244 + ... + 40775.

It is an arithmetic number, because the mean of its divisors is an integer number (2430600).

Almost surely, 2^21551054 is an apocalyptic number.

21551054 is a deficient number, since it is larger than the sum of its proper divisors (17338546).

21551054 is a wasteful number, since it uses less digits than its factorization.

21551054 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81047.

The product of its (nonzero) digits is 1000, while the sum is 23.

The square root of 21551054 is about 4642.3112778012. The cubic root of 21551054 is about 278.2848123993.

Adding to 21551054 its reverse (45015512), we get a palindrome (66566566).

The spelling of 21551054 in words is "twenty-one million, five hundred fifty-one thousand, fifty-four".