20145870 has 24 divisors (see below), whose sum is σ = 52379496. Its totient is φ = 5372208.

The previous prime is 20145863. The next prime is 20145889. The reversal of 20145870 is 7854102.

20145870 is a `hidden beast` number, since 201 + 458 + 7 + 0 = 666.

It is a plaindrome in base 16.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 111832 + ... + 112011.

It is an arithmetic number, because the mean of its divisors is an integer number (2182479).

Almost surely, 2^20145870 is an apocalyptic number.

20145870 is an abundant number, since it is smaller than the sum of its proper divisors (32233626).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20145870 is a wasteful number, since it uses less digits than its factorization.

20145870 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 223856 (or 223853 counting only the distinct ones).

The product of its (nonzero) digits is 2240, while the sum is 27.

The square root of 20145870 is about 4488.4150877565. The cubic root of 20145870 is about 272.1000839159.

Adding to 20145870 its reverse (7854102), we get a palindrome (27999972).

The spelling of 20145870 in words is "twenty million, one hundred forty-five thousand, eight hundred seventy".