2400991 has 4 divisors (see below), whose sum is σ = 2456872. Its totient is φ = 2345112.

The previous prime is 2400989. The next prime is 2401013. The reversal of 2400991 is 1990042.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 2400991 - 2¹ = 2400989 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2400971) 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, 27876 + ... + 27961.

It is an arithmetic number, because the mean of its divisors is an integer number (614218).

2^2400991 is an apocalyptic number.

2400991 is a deficient number, since it is larger than the sum of its proper divisors (55881).

2400991 is an equidigital number, since it uses as much as digits as its factorization.

2400991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55880.

The product of its (nonzero) digits is 648, while the sum is 25.

The square root of 2400991 is about 1549.5131493472. The cubic root of 2400991 is about 133.9050154821.

It can be divided in two parts, 240099 and 1, that added together give a square (240100 = 490²).

The spelling of 2400991 in words is "two million, four hundred thousand, nine hundred ninety-one".