20436478 has 4 divisors (see below), whose sum is σ = 30654720. Its totient is φ = 10218238.

The previous prime is 20436473. The next prime is 20436487. The reversal of 20436478 is 87463402.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20436473) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5109118 + ... + 5109121.

It is an arithmetic number, because the mean of its divisors is an integer number (7663680).

Almost surely, 2^20436478 is an apocalyptic number.

20436478 is a deficient number, since it is larger than the sum of its proper divisors (10218242).

20436478 is a wasteful number, since it uses less digits than its factorization.

20436478 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10218241.

The product of its (nonzero) digits is 32256, while the sum is 34.

The square root of 20436478 is about 4520.6722951349. The cubic root of 20436478 is about 273.4022078402.

The spelling of 20436478 in words is "twenty million, four hundred thirty-six thousand, four hundred seventy-eight".