220210002100021 has 4 divisors (see below), whose sum is σ = 220210161824044. Its totient is φ = 220209842376000.

The previous prime is 220210002099979. The next prime is 220210002100073. The reversal of 220210002100021 is 120001200012022.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 142219219824900 + 77990782275121 = 11925570^2 + 8831239^2 .

It is a cyclic number.

It is not a de Polignac number, because 220210002100021 - 2¹³ = 220210002091829 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 220210002099974 and 220210002100010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (220210002104021) 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, 77775810 + ... + 80557411.

It is an arithmetic number, because the mean of its divisors is an integer number (55052540456011).

Almost surely, 2^{220210002100021} is an apocalyptic number.

It is an amenable number.

220210002100021 is a deficient number, since it is larger than the sum of its proper divisors (159724023).

220210002100021 is a wasteful number, since it uses less digits than its factorization.

220210002100021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 159724022.

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 220210002100021 its reverse (120001200012022), we get a palindrome (340211202112043).

The spelling of 220210002100021 in words is "two hundred twenty trillion, two hundred ten billion, two million, one hundred thousand, twenty-one".