2115621 has 6 divisors (see below), whose sum is σ = 3055910. Its totient is φ = 1410408.

The previous prime is 2115571. The next prime is 2115629. The reversal of 2115621 is 1265112.

It can be written as a sum of positive squares in only one way, i.e., 1718721 + 396900 = 1311^2 + 630^2 .

It is not a de Polignac number, because 2115621 - 2⁷ = 2115493 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2115594 and 2115603.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2115629) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 117526 + ... + 117543.

2^2115621 is an apocalyptic number.

It is an amenable number.

2115621 is a deficient number, since it is larger than the sum of its proper divisors (940289).

2115621 is a wasteful number, since it uses less digits than its factorization.

2115621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 235075 (or 235072 counting only the distinct ones).

The product of its digits is 120, while the sum is 18.

The square root of 2115621 is about 1454.5174457531. The cubic root of 2115621 is about 128.3746550842.

It can be divided in two parts, 211 and 5621, that added together give a cube (5832 = 18³).

The spelling of 2115621 in words is "two million, one hundred fifteen thousand, six hundred twenty-one".