18861959 has 8 divisors (see below), whose sum is σ = 20246400. Its totient is φ = 17508096.

The previous prime is 18861949. The next prime is 18861967. The reversal of 18861959 is 95916881.

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

It is not a de Polignac number, because 18861959 - 2⁴ = 18861943 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 (18861949) 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, 6359 + ... + 8840.

It is an arithmetic number, because the mean of its divisors is an integer number (2530800).

Almost surely, 2^18861959 is an apocalyptic number.

18861959 is a deficient number, since it is larger than the sum of its proper divisors (1384441).

18861959 is a wasteful number, since it uses less digits than its factorization.

18861959 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15289.

The product of its digits is 155520, while the sum is 47.

The square root of 18861959 is about 4343.0356894688. The cubic root of 18861959 is about 266.1923674915.

The spelling of 18861959 in words is "eighteen million, eight hundred sixty-one thousand, nine hundred fifty-nine".