20263645 has 8 divisors (see below), whose sum is σ = 24540120. Its totient is φ = 16061760.

The previous prime is 20263637. The next prime is 20263657. The reversal of 20263645 is 54636202.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 2056356 + 18207289 = 1434^2 + 4267^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20263645 - 2³ = 20263637 is a prime.

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, 18046 + ... + 19135.

It is an arithmetic number, because the mean of its divisors is an integer number (3067515).

Almost surely, 2^20263645 is an apocalyptic number.

It is an amenable number.

20263645 is a deficient number, since it is larger than the sum of its proper divisors (4276475).

20263645 is a wasteful number, since it uses less digits than its factorization.

20263645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37295.

The product of its (nonzero) digits is 8640, while the sum is 28.

The square root of 20263645 is about 4501.5158557979. The cubic root of 20263645 is about 272.6292964396.

Adding to 20263645 its reverse (54636202), we get a palindrome (74899847).

It can be divided in two parts, 2026 and 3645, that added together give a triangular number (5671 = T₁₀₆).

The spelling of 20263645 in words is "twenty million, two hundred sixty-three thousand, six hundred forty-five".