1240905 has 8 divisors (see below), whose sum is σ = 1985472. Its totient is φ = 661808.

The previous prime is 1240861. The next prime is 1240931. The reversal of 1240905 is 5090421.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1240905 - 2⁷ = 1240777 is a prime.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 41349 + ... + 41378.

It is an arithmetic number, because the mean of its divisors is an integer number (248184).

2^1240905 is an apocalyptic number.

1240905 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1240905 is a deficient number, since it is larger than the sum of its proper divisors (744567).

1240905 is an equidigital number, since it uses as much as digits as its factorization.

1240905 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82735.

The product of its (nonzero) digits is 360, while the sum is 21.

The square root of 1240905 is about 1113.9591554451. The cubic root of 1240905 is about 107.4598371691.

It can be divided in two parts, 1240 and 905, that added together give a triangular number (2145 = T₆₅).

The spelling of 1240905 in words is "one million, two hundred forty thousand, nine hundred five".