20929161 has 32 divisors (see below), whose sum is σ = 31890816. Its totient is φ = 12096000.

The previous prime is 20929157. The next prime is 20929171. The reversal of 20929161 is 16192902.

It is a happy number.

It is not a de Polignac number, because 20929161 - 2² = 20929157 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20929121) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 74341 + ... + 74621.

It is an arithmetic number, because the mean of its divisors is an integer number (996588).

Almost surely, 2^20929161 is an apocalyptic number.

It is an amenable number.

20929161 is a deficient number, since it is larger than the sum of its proper divisors (10961655).

20929161 is a wasteful number, since it uses less digits than its factorization.

20929161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 393.

The product of its (nonzero) digits is 1944, while the sum is 30.

The square root of 20929161 is about 4574.8399972021. The cubic root of 20929161 is about 275.5818468442.

The spelling of 20929161 in words is "twenty million, nine hundred twenty-nine thousand, one hundred sixty-one".