20905154 has 4 divisors (see below), whose sum is σ = 31357734. Its totient is φ = 10452576.

The previous prime is 20905153. The next prime is 20905193. The reversal of 20905154 is 45150902.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 14025025 + 6880129 = 3745^2 + 2623^2 .

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20905153) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5226287 + ... + 5226290.

Almost surely, 2^20905154 is an apocalyptic number.

20905154 is a deficient number, since it is larger than the sum of its proper divisors (10452580).

20905154 is a wasteful number, since it uses less digits than its factorization.

20905154 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10452579.

The product of its (nonzero) digits is 1800, while the sum is 26.

The square root of 20905154 is about 4572.2154367440. The cubic root of 20905154 is about 275.4764369073.

The spelling of 20905154 in words is "twenty million, nine hundred five thousand, one hundred fifty-four".