21521102 has 4 divisors (see below), whose sum is σ = 32281656. Its totient is φ = 10760550.

The previous prime is 21521083. The next prime is 21521111. The reversal of 21521102 is 20112512.

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

It is a congruent number.

It is an unprimeable number.

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, 5380274 + ... + 5380277.

It is an arithmetic number, because the mean of its divisors is an integer number (8070414).

Almost surely, 2^21521102 is an apocalyptic number.

21521102 is a deficient number, since it is larger than the sum of its proper divisors (10760554).

21521102 is a wasteful number, since it uses less digits than its factorization.

21521102 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10760553.

The product of its (nonzero) digits is 40, while the sum is 14.

The square root of 21521102 is about 4639.0841768608. The cubic root of 21521102 is about 278.1558310643.

Adding to 21521102 its reverse (20112512), we get a palindrome (41633614).

The spelling of 21521102 in words is "twenty-one million, five hundred twenty-one thousand, one hundred two".