20636390 has 16 divisors (see below), whose sum is σ = 38344320. Its totient is φ = 7988160.

The previous prime is 20636389. The next prime is 20636401. The reversal of 20636390 is 9363602.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 32975 + ... + 33594.

It is an arithmetic number, because the mean of its divisors is an integer number (2396520).

Almost surely, 2^20636390 is an apocalyptic number.

20636390 is a deficient number, since it is larger than the sum of its proper divisors (17707930).

20636390 is a wasteful number, since it uses less digits than its factorization.

20636390 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66607.

The product of its (nonzero) digits is 5832, while the sum is 29.

The square root of 20636390 is about 4542.7293557948. The cubic root of 20636390 is about 274.2908007128.

Adding to 20636390 its reverse (9363602), we get a palindrome (29999992).

The spelling of 20636390 in words is "twenty million, six hundred thirty-six thousand, three hundred ninety".