18440697 has 16 divisors (see below), whose sum is σ = 28235520. Its totient is φ = 10587600.

The previous prime is 18440677. The next prime is 18440707. The reversal of 18440697 is 79604481.

It is a happy number.

It is not a de Polignac number, because 18440697 - 2⁶ = 18440633 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18440647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14079 + ... + 15332.

It is an arithmetic number, because the mean of its divisors is an integer number (1764720).

Almost surely, 2^18440697 is an apocalyptic number.

It is an amenable number.

18440697 is a deficient number, since it is larger than the sum of its proper divisors (9794823).

18440697 is a wasteful number, since it uses less digits than its factorization.

18440697 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29444.

The product of its (nonzero) digits is 48384, while the sum is 39.

The square root of 18440697 is about 4294.2632662658. The cubic root of 18440697 is about 264.1957197638.

The spelling of 18440697 in words is "eighteen million, four hundred forty thousand, six hundred ninety-seven".