2621161 has 3 divisors (see below), whose sum is σ = 2622781.
Its totient is φ = 2619542.
The previous prime is 2621159. The next prime is 2621167. The reversal of 2621161 is 1611262.
The square root of 2621161 is 1619.
It is a perfect power (a square), and thus also a powerful number.
It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.
It is not a de Polignac number, because 2621161 - 21 = 2621159 is a prime.
It is an Ulam number.
It is a Duffinian number.
It is not an unprimeable number, because it can be changed into a prime (2621167) by changing a digit.
It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 810 + ... + 2428.
22621161 is an apocalyptic number.
2621161 is the 1619-th square number.
2621161 is the 810-th centered octagonal number.
It is an amenable number.
2621161 is a deficient number, since it is larger than the sum of its proper divisors (1620).
2621161 is an frugal number, since it uses more digits than its factorization.
2621161 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 3238 (or 1619 counting only the distinct ones).
The product of its digits is 144, while the sum is 19.
The cubic root of 2621161 is about 137.8789283277.
Multiplying 2621161 by its product of digits (144), we get a square (377447184 = 194282).
The spelling of 2621161 in words is "two million, six hundred twenty-one thousand, one hundred sixty-one".