20613994 has 4 divisors (see below), whose sum is σ = 30920994. Its totient is φ = 10306996.

The previous prime is 20613949. The next prime is 20613997. The reversal of 20613994 is 49931602.

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., 11390625 + 9223369 = 3375^2 + 3037^2 .

It is not an unprimeable number, because it can be changed into a prime (20613997) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5153497 + ... + 5153500.

Almost surely, 2^20613994 is an apocalyptic number.

20613994 is a deficient number, since it is larger than the sum of its proper divisors (10307000).

20613994 is a wasteful number, since it uses less digits than its factorization.

20613994 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10306999.

The product of its (nonzero) digits is 11664, while the sum is 34.

The square root of 20613994 is about 4540.2636487323. The cubic root of 20613994 is about 274.1915385132.

The spelling of 20613994 in words is "twenty million, six hundred thirteen thousand, nine hundred ninety-four".