2020172621 has 4 divisors (see below), whose sum is σ = 2021384700. Its totient is φ = 2018960544.

The previous prime is 2020172603. The next prime is 2020172711. The reversal of 2020172621 is 1262710202.

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 760987396 + 1259185225 = 27586^2 + 35485^2 .

It is a cyclic number.

It is not a de Polignac number, because 2020172621 - 2²⁶ = 1953063757 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 (2020172821) 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, 603536 + ... + 606873.

It is an arithmetic number, because the mean of its divisors is an integer number (505346175).

Almost surely, 2^2020172621 is an apocalyptic number.

It is an amenable number.

2020172621 is a deficient number, since it is larger than the sum of its proper divisors (1212079).

2020172621 is a wasteful number, since it uses less digits than its factorization.

2020172621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1212078.

The product of its (nonzero) digits is 672, while the sum is 23.

The square root of 2020172621 is about 44946.3304508833. The cubic root of 2020172621 is about 1264.1428723180.

Adding to 2020172621 its reverse (1262710202), we get a palindrome (3282882823).

The spelling of 2020172621 in words is "two billion, twenty million, one hundred seventy-two thousand, six hundred twenty-one".