20618386 has 4 divisors (see below), whose sum is σ = 30927582. Its totient is φ = 10309192.

The previous prime is 20618369. The next prime is 20618387. The reversal of 20618386 is 68381602.

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., 17065161 + 3553225 = 4131^2 + 1885^2 .

It is not an unprimeable number, because it can be changed into a prime (20618387) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5154595 + ... + 5154598.

Almost surely, 2^20618386 is an apocalyptic number.

20618386 is a deficient number, since it is larger than the sum of its proper divisors (10309196).

20618386 is a wasteful number, since it uses less digits than its factorization.

20618386 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10309195.

The product of its (nonzero) digits is 13824, while the sum is 34.

The square root of 20618386 is about 4540.7472953249. The cubic root of 20618386 is about 274.2110101356.

Adding to 20618386 its reverse (68381602), we get a palindrome (88999988).

The spelling of 20618386 in words is "twenty million, six hundred eighteen thousand, three hundred eighty-six".