20631794 has 4 divisors (see below), whose sum is σ = 30947694. Its totient is φ = 10315896.

The previous prime is 20631781. The next prime is 20631797. The reversal of 20631794 is 49713602.

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., 13140625 + 7491169 = 3625^2 + 2737^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 20631794.

It is not an unprimeable number, because it can be changed into a prime (20631797) 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, 5157947 + ... + 5157950.

Almost surely, 2^20631794 is an apocalyptic number.

20631794 is a deficient number, since it is larger than the sum of its proper divisors (10315900).

20631794 is a wasteful number, since it uses less digits than its factorization.

20631794 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10315899.

The product of its (nonzero) digits is 9072, while the sum is 32.

The square root of 20631794 is about 4542.2234643399. The cubic root of 20631794 is about 274.2704364579.

The spelling of 20631794 in words is "twenty million, six hundred thirty-one thousand, seven hundred ninety-four".