2621661 has 16 divisors (see below), whose sum is σ = 4030464. Its totient is φ = 1484784.

The previous prime is 2621617. The next prime is 2621669. The reversal of 2621661 is 1661262.

It is not a de Polignac number, because 2621661 - 2¹⁰ = 2620637 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2621669) 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, 2176 + ... + 3158.

It is an arithmetic number, because the mean of its divisors is an integer number (251904).

2^2621661 is an apocalyptic number.

2621661 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

2621661 is a deficient number, since it is larger than the sum of its proper divisors (1408803).

2621661 is a wasteful number, since it uses less digits than its factorization.

2621661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1120.

The product of its digits is 864, while the sum is 24.

The square root of 2621661 is about 1619.1544089431. The cubic root of 2621661 is about 137.8876948096.

The spelling of 2621661 in words is "two million, six hundred twenty-one thousand, six hundred sixty-one".