18440661 has 8 divisors (see below), whose sum is σ = 25051680. Its totient is φ = 12061712.

The previous prime is 18440651. The next prime is 18440663. The reversal of 18440661 is 16604481.

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 18440661 - 2¹¹ = 18438613 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18440663) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 57831 + ... + 58148.

It is an arithmetic number, because the mean of its divisors is an integer number (3131460).

Almost surely, 2^18440661 is an apocalyptic number.

It is an amenable number.

18440661 is a deficient number, since it is larger than the sum of its proper divisors (6611019).

18440661 is a wasteful number, since it uses less digits than its factorization.

18440661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 116035.

The product of its (nonzero) digits is 4608, while the sum is 30.

The square root of 18440661 is about 4294.2590746251. The cubic root of 18440661 is about 264.1955478424.

The spelling of 18440661 in words is "eighteen million, four hundred forty thousand, six hundred sixty-one".