2660921 has 4 divisors (see below), whose sum is σ = 2673744. Its totient is φ = 2648100.

The previous prime is 2660899. The next prime is 2660963. The reversal of 2660921 is 1290662.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 2660921 - 2¹⁸ = 2398777 is a prime.

It is a super-4 number, since 4×2660921⁴ (a number of 27 digits) contains 4444 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2660521) 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, 6095 + ... + 6516.

It is an arithmetic number, because the mean of its divisors is an integer number (668436).

2^2660921 is an apocalyptic number.

It is an amenable number.

2660921 is a deficient number, since it is larger than the sum of its proper divisors (12823).

2660921 is a wasteful number, since it uses less digits than its factorization.

2660921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12822.

The product of its (nonzero) digits is 1296, while the sum is 26.

The square root of 2660921 is about 1631.2329692598. The cubic root of 2660921 is about 138.5725876850.

The spelling of 2660921 in words is "two million, six hundred sixty thousand, nine hundred twenty-one".