21563054 has 4 divisors (see below), whose sum is σ = 32344584. Its totient is φ = 10781526.

The previous prime is 21563053. The next prime is 21563057. The reversal of 21563054 is 45036512.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21563051) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5390762 + ... + 5390765.

It is an arithmetic number, because the mean of its divisors is an integer number (8086146).

Almost surely, 2^21563054 is an apocalyptic number.

21563054 is a deficient number, since it is larger than the sum of its proper divisors (10781530).

21563054 is a wasteful number, since it uses less digits than its factorization.

21563054 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10781529.

The product of its (nonzero) digits is 3600, while the sum is 26.

The square root of 21563054 is about 4643.6035575833. The cubic root of 21563054 is about 278.3364540827.

Adding to 21563054 its reverse (45036512), we get a palindrome (66599566).

The spelling of 21563054 in words is "twenty-one million, five hundred sixty-three thousand, fifty-four".