18496991 has 16 divisors (see below), whose sum is σ = 20072448. Its totient is φ = 17001600.

The previous prime is 18496979. The next prime is 18496999. The reversal of 18496991 is 19969481.

It is not a de Polignac number, because 18496991 - 2¹⁸ = 18234847 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (47).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18496999) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 76631 + ... + 76871.

It is an arithmetic number, because the mean of its divisors is an integer number (1254528).

Almost surely, 2^18496991 is an apocalyptic number.

18496991 is a deficient number, since it is larger than the sum of its proper divisors (1575457).

18496991 is a wasteful number, since it uses less digits than its factorization.

18496991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 382.

The product of its digits is 139968, while the sum is 47.

The square root of 18496991 is about 4300.8128301520. The cubic root of 18496991 is about 264.4642838270.

The spelling of 18496991 in words is "eighteen million, four hundred ninety-six thousand, nine hundred ninety-one".