21221010983 has 4 divisors (see below), whose sum is σ = 21283981680. Its totient is φ = 21158040288.

The previous prime is 21221010977. The next prime is 21221010997. The reversal of 21221010983 is 38901012212.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21221010983 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21221060983) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 31484843 + ... + 31485516.

It is an arithmetic number, because the mean of its divisors is an integer number (5320995420).

Almost surely, 2^21221010983 is an apocalyptic number.

21221010983 is a deficient number, since it is larger than the sum of its proper divisors (62970697).

21221010983 is an equidigital number, since it uses as much as digits as its factorization.

21221010983 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 62970696.

The product of its (nonzero) digits is 1728, while the sum is 29.

The spelling of 21221010983 in words is "twenty-one billion, two hundred twenty-one million, ten thousand, nine hundred eighty-three".