2231621 has 16 divisors (see below), whose sum is σ = 2709504. Its totient is φ = 1796784.

The previous prime is 2231617. The next prime is 2231623. The reversal of 2231621 is 1261322.

2231621 = T₇₉₅ + T₇₉₆ + ... + T₈₀₁.

It is not a de Polignac number, because 2231621 - 2² = 2231617 is a prime.

It is a super-3 number, since 3×2231621³ = 33341303387633088183, which contains 333 as substring.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 2231621.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2231623) 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, 13280 + ... + 13446.

It is an arithmetic number, because the mean of its divisors is an integer number (169344).

2^2231621 is an apocalyptic number.

It is an amenable number.

2231621 is a deficient number, since it is larger than the sum of its proper divisors (477883).

2231621 is a wasteful number, since it uses less digits than its factorization.

2231621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 280.

The product of its digits is 144, while the sum is 17.

The square root of 2231621 is about 1493.8611046546. The cubic root of 2231621 is about 130.6793041308.

Adding to 2231621 its reverse (1261322), we get a palindrome (3492943).

Subtracting from 2231621 its reverse (1261322), we obtain a cube (970299 = 99³).

The spelling of 2231621 in words is "two million, two hundred thirty-one thousand, six hundred twenty-one".