20617994 has 4 divisors (see below), whose sum is σ = 30926994. Its totient is φ = 10308996.

The previous prime is 20617981. The next prime is 20617999. The reversal of 20617994 is 49971602.

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., 16362025 + 4255969 = 4045^2 + 2063^2 .

It is not an unprimeable number, because it can be changed into a prime (20617999) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5154497 + ... + 5154500.

Almost surely, 2^20617994 is an apocalyptic number.

20617994 is a deficient number, since it is larger than the sum of its proper divisors (10309000).

20617994 is a wasteful number, since it uses less digits than its factorization.

20617994 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10308999.

The product of its (nonzero) digits is 27216, while the sum is 38.

The square root of 20617994 is about 4540.7041304185. The cubic root of 20617994 is about 274.2092723437.

The spelling of 20617994 in words is "twenty million, six hundred seventeen thousand, nine hundred ninety-four".