18997901 has 8 divisors (see below), whose sum is σ = 20795544. Its totient is φ = 17248320.

The previous prime is 18997897. The next prime is 18997919. The reversal of 18997901 is 10979981.

It can be written as a sum of positive squares in 4 ways, for example, as 84100 + 18913801 = 290^2 + 4349^2 .

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 18997901 - 2² = 18997897 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 (18997991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11186 + ... + 12771.

It is an arithmetic number, because the mean of its divisors is an integer number (2599443).

Almost surely, 2^18997901 is an apocalyptic number.

It is an amenable number.

18997901 is a deficient number, since it is larger than the sum of its proper divisors (1797643).

18997901 is a wasteful number, since it uses less digits than its factorization.

18997901 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24031.

The product of its (nonzero) digits is 40824, while the sum is 44.

The square root of 18997901 is about 4358.6581650779. The cubic root of 18997901 is about 266.8303382383.

The spelling of 18997901 in words is "eighteen million, nine hundred ninety-seven thousand, nine hundred one".