2640729 has 32 divisors (see below), whose sum is σ = 4596480. Its totient is φ = 1308672.

The previous prime is 2640721. The next prime is 2640739. The reversal of 2640729 is 9270462.

It is a happy number.

It is not a de Polignac number, because 2640729 - 2³ = 2640721 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 2640696 and 2640705.

It is not an unprimeable number, because it can be changed into a prime (2640721) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4357 + ... + 4925.

It is an arithmetic number, because the mean of its divisors is an integer number (143640).

2^2640729 is an apocalyptic number.

It is an amenable number.

2640729 is a deficient number, since it is larger than the sum of its proper divisors (1955751).

2640729 is a wasteful number, since it uses less digits than its factorization.

2640729 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 609.

The product of its (nonzero) digits is 6048, while the sum is 30.

The square root of 2640729 is about 1625.0319996849. The cubic root of 2640729 is about 138.2211848904.

It can be divided in two parts, 26 and 40729, that added together give a triangular number (40755 = T₂₈₅).

The spelling of 2640729 in words is "two million, six hundred forty thousand, seven hundred twenty-nine".