18897705 has 40 divisors (see below), whose sum is σ = 35065800. Its totient is φ = 9725184.

The previous prime is 18897701. The next prime is 18897709. The reversal of 18897705 is 50779881.

It is an interprime number because it is at equal distance from previous prime (18897701) and next prime (18897709).

It can be written as a sum of positive squares in 4 ways, for example, as 6953769 + 11943936 = 2637^2 + 3456^2 .

It is not a de Polignac number, because 18897705 - 2² = 18897701 is a prime.

It is a super-3 number, since 3×18897705³ (a number of 23 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (18897701) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 10941 + ... + 12549.

It is an arithmetic number, because the mean of its divisors is an integer number (876645).

Almost surely, 2^18897705 is an apocalyptic number.

18897705 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

18897705 is a deficient number, since it is larger than the sum of its proper divisors (16168095).

18897705 is a wasteful number, since it uses less digits than its factorization.

18897705 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1655 (or 1646 counting only the distinct ones).

The product of its (nonzero) digits is 141120, while the sum is 45.

The square root of 18897705 is about 4347.1490657671. The cubic root of 18897705 is about 266.3604183949.

The spelling of 18897705 in words is "eighteen million, eight hundred ninety-seven thousand, seven hundred five".