220120021 has 16 divisors (see below), whose sum is σ = 247032576. Its totient is φ = 194400000.

The previous prime is 220120003. The next prime is 220120027. The reversal of 220120021 is 120021022.

It is a 5-Lehmer number, since φ(220120021) divides (220120021-1)⁵.

It is a cyclic number.

It is not a de Polignac number, because 220120021 - 2¹¹ = 220117973 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 (220120027) 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, 121321 + ... + 123121.

It is an arithmetic number, because the mean of its divisors is an integer number (15439536).

Almost surely, 2^220120021 is an apocalyptic number.

It is an amenable number.

220120021 is a deficient number, since it is larger than the sum of its proper divisors (26912555).

220120021 is a wasteful number, since it uses less digits than its factorization.

220120021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2124.

The product of its (nonzero) digits is 16, while the sum is 10.

The square root of 220120021 is about 14836.4423296153. The cubic root of 220120021 is about 603.7908331257.

Adding to 220120021 its reverse (120021022), we get a palindrome (340141043).

It can be divided in two parts, 2201 and 20021, that added together give a palindrome (22222).

The spelling of 220120021 in words is "two hundred twenty million, one hundred twenty thousand, twenty-one".