21221101009973 has 16 divisors (see below), whose sum is σ = 22858363278336. Its totient is φ = 19643405886720.

The previous prime is 21221101009891. The next prime is 21221101009981. The reversal of 21221101009973 is 37990010112212.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 21221101009973 - 2³⁰ = 21220027268149 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 (21221101009993) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 79163915 + ... + 79431527.

It is an arithmetic number, because the mean of its divisors is an integer number (1428647704896).

Almost surely, 2^{21221101009973} is an apocalyptic number.

21221101009973 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

It is an amenable number.

21221101009973 is a deficient number, since it is larger than the sum of its proper divisors (1637262268363).

21221101009973 is a wasteful number, since it uses less digits than its factorization.

21221101009973 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 378884.

The product of its (nonzero) digits is 13608, while the sum is 38.

The spelling of 21221101009973 in words is "twenty-one trillion, two hundred twenty-one billion, one hundred one million, nine thousand, nine hundred seventy-three".