20154985 has 8 divisors (see below), whose sum is σ = 24776136. Its totient is φ = 15730560.

The previous prime is 20154961. The next prime is 20155021. The reversal of 20154985 is 58945102.

It can be written as a sum of positive squares in 4 ways, for example, as 120409 + 20034576 = 347^2 + 4476^2 .

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

It is not a de Polignac number, because 20154985 - 2⁹ = 20154473 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20154985.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 48954 + ... + 49363.

It is an arithmetic number, because the mean of its divisors is an integer number (3097017).

Almost surely, 2^20154985 is an apocalyptic number.

It is an amenable number.

20154985 is a deficient number, since it is larger than the sum of its proper divisors (4621151).

20154985 is an equidigital number, since it uses as much as digits as its factorization.

20154985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 98363.

The product of its (nonzero) digits is 14400, while the sum is 34.

The square root of 20154985 is about 4489.4303647568. The cubic root of 20154985 is about 272.1411149610.

The spelling of 20154985 in words is "twenty million, one hundred fifty-four thousand, nine hundred eighty-five".