20670545 has 16 divisors (see below), whose sum is σ = 28425600. Its totient is φ = 14135424.

The previous prime is 20670523. The next prime is 20670547. The reversal of 20670545 is 54507602.

It is a cyclic number.

It is not a de Polignac number, because 20670545 - 2²⁰ = 19621969 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20670547) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19181 + ... + 20229.

It is an arithmetic number, because the mean of its divisors is an integer number (1776600).

Almost surely, 2^20670545 is an apocalyptic number.

It is an amenable number.

20670545 is a deficient number, since it is larger than the sum of its proper divisors (7755055).

20670545 is a wasteful number, since it uses less digits than its factorization.

20670545 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1624.

The product of its (nonzero) digits is 8400, while the sum is 29.

The square root of 20670545 is about 4546.4871054475. The cubic root of 20670545 is about 274.4420422581.

The spelling of 20670545 in words is "twenty million, six hundred seventy thousand, five hundred forty-five".