20601978 has 16 divisors (see below), whose sum is σ = 41419776. Its totient is φ = 6831360.

The previous prime is 20601961. The next prime is 20601979. The reversal of 20601978 is 87910602.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20601979) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7738 + ... + 10053.

It is an arithmetic number, because the mean of its divisors is an integer number (2588736).

Almost surely, 2^20601978 is an apocalyptic number.

20601978 is an abundant number, since it is smaller than the sum of its proper divisors (20817798).

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

20601978 is a wasteful number, since it uses less digits than its factorization.

20601978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17989.

The product of its (nonzero) digits is 6048, while the sum is 33.

The square root of 20601978 is about 4538.9401846687. The cubic root of 20601978 is about 274.1382522861.

The spelling of 20601978 in words is "twenty million, six hundred one thousand, nine hundred seventy-eight".