21021220212193 has 8 divisors (see below), whose sum is σ = 21367663977960. Its totient is φ = 20674835594880.

The previous prime is 21021220212143. The next prime is 21021220212227. The reversal of 21021220212193 is 39121202212012.

It can be written as a sum of positive squares in 4 ways, for example, as 10987861329 + 21010232350864 = 104823^2 + 4583692^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21021220212193 - 2³⁷ = 20883781258721 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21021220212143) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14070178 + ... + 15492331.

It is an arithmetic number, because the mean of its divisors is an integer number (2670957997245).

Almost surely, 2^{21021220212193} is an apocalyptic number.

It is an amenable number.

21021220212193 is a deficient number, since it is larger than the sum of its proper divisors (346443765767).

21021220212193 is a wasteful number, since it uses less digits than its factorization.

21021220212193 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29574227.

The product of its (nonzero) digits is 1728, while the sum is 28.

The spelling of 21021220212193 in words is "twenty-one trillion, twenty-one billion, two hundred twenty million, two hundred twelve thousand, one hundred ninety-three".