21162554 has 16 divisors (see below), whose sum is σ = 36777408. Its totient is φ = 8944992.

The previous prime is 21162551. The next prime is 21162613. The reversal of 21162554 is 45526112.

It is not an unprimeable number, because it can be changed into a prime (21162551) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9332 + ... + 11375.

It is an arithmetic number, because the mean of its divisors is an integer number (2298588).

Almost surely, 2^21162554 is an apocalyptic number.

21162554 is a deficient number, since it is larger than the sum of its proper divisors (15614854).

21162554 is a wasteful number, since it uses less digits than its factorization.

21162554 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20789.

The product of its digits is 2400, while the sum is 26.

The square root of 21162554 is about 4600.2776003194. The cubic root of 21162554 is about 276.6024524766.

Adding to 21162554 its reverse (45526112), we get a palindrome (66688666).

The spelling of 21162554 in words is "twenty-one million, one hundred sixty-two thousand, five hundred fifty-four".