21063156 has 12 divisors (see below), whose sum is σ = 49147392. Its totient is φ = 7021048.

The previous prime is 21063149. The next prime is 21063169. The reversal of 21063156 is 65136012.

It is a tau number, because it is divible by the number of its divisors (12).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 877620 + ... + 877643.

It is an arithmetic number, because the mean of its divisors is an integer number (4095616).

Almost surely, 2^21063156 is an apocalyptic number.

It is an amenable number.

21063156 is an abundant number, since it is smaller than the sum of its proper divisors (28084236).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21063156 is a wasteful number, since it uses less digits than its factorization.

21063156 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1755270 (or 1755268 counting only the distinct ones).

The product of its (nonzero) digits is 1080, while the sum is 24.

The square root of 21063156 is about 4589.4614063090. The cubic root of 21063156 is about 276.1687164198.

Adding to 21063156 its reverse (65136012), we get a palindrome (86199168).

The spelling of 21063156 in words is "twenty-one million, sixty-three thousand, one hundred fifty-six".