20556535 has 8 divisors (see below), whose sum is σ = 24692976. Its totient is φ = 16428480.

The previous prime is 20556533. The next prime is 20556541. The reversal of 20556535 is 53565502.

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

It is not a de Polignac number, because 20556535 - 2¹ = 20556533 is a prime.

It is a super-2 number, since 2×20556535² = 845142262412450, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20556497 and 20556506.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20556533) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6547 + ... + 9163.

It is an arithmetic number, because the mean of its divisors is an integer number (3086622).

Almost surely, 2^20556535 is an apocalyptic number.

20556535 is a deficient number, since it is larger than the sum of its proper divisors (4136441).

20556535 is a wasteful number, since it uses less digits than its factorization.

20556535 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4193.

The product of its (nonzero) digits is 22500, while the sum is 31.

The square root of 20556535 is about 4533.9315169067. The cubic root of 20556535 is about 273.9365429264.

The spelling of 20556535 in words is "twenty million, five hundred fifty-six thousand, five hundred thirty-five".