2690681 has 4 divisors (see below), whose sum is σ = 3075072. Its totient is φ = 2306292.

The previous prime is 2690671. The next prime is 2690689. The reversal of 2690681 is 1860962.

2690681 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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, and also an emirpimes, since its reverse is a distinct semiprime: 1860962 = 2 ⋅930481.

It is a cyclic number.

It is not a de Polignac number, because 2690681 - 2¹⁰ = 2689657 is a prime.

It is a super-2 number, since 2×2690681² = 14479528487522, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2690689) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 192185 + ... + 192198.

It is an arithmetic number, because the mean of its divisors is an integer number (768768).

2^2690681 is an apocalyptic number.

It is an amenable number.

2690681 is a deficient number, since it is larger than the sum of its proper divisors (384391).

2690681 is an equidigital number, since it uses as much as digits as its factorization.

2690681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 384390.

The product of its (nonzero) digits is 5184, while the sum is 32.

The square root of 2690681 is about 1640.3295400620. The cubic root of 2690681 is about 139.0872767619.

It can be divided in two parts, 26 and 90681, that multiplied together give a triangular number (2357706 = T₂₁₇₁).

The spelling of 2690681 in words is "two million, six hundred ninety thousand, six hundred eighty-one".