20431634 has 4 divisors (see below), whose sum is σ = 30647454. Its totient is φ = 10215816.

The previous prime is 20431627. The next prime is 20431639. The reversal of 20431634 is 43613402.

It is a happy number.

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., 19228225 + 1203409 = 4385^2 + 1097^2 .

It is not an unprimeable number, because it can be changed into a prime (20431639) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5107907 + ... + 5107910.

Almost surely, 2^20431634 is an apocalyptic number.

20431634 is a deficient number, since it is larger than the sum of its proper divisors (10215820).

20431634 is a wasteful number, since it uses less digits than its factorization.

20431634 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10215819.

The product of its (nonzero) digits is 1728, while the sum is 23.

The square root of 20431634 is about 4520.1365023636. The cubic root of 20431634 is about 273.3806048852.

The spelling of 20431634 in words is "twenty million, four hundred thirty-one thousand, six hundred thirty-four".