20578069 has 4 divisors (see below), whose sum is σ = 20591820. Its totient is φ = 20564320.

The previous prime is 20578067. The next prime is 20578073. The reversal of 20578069 is 96087502.

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

It can be written as a sum of positive squares in 2 ways, for example, as 8236900 + 12341169 = 2870^2 + 3513^2 .

It is a cyclic number.

It is not a de Polignac number, because 20578069 - 2¹ = 20578067 is a prime.

It is a super-2 number, since 2×20578069² = 846913847537522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20578067) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4312 + ... + 7729.

It is an arithmetic number, because the mean of its divisors is an integer number (5147955).

Almost surely, 2^20578069 is an apocalyptic number.

It is an amenable number.

20578069 is a deficient number, since it is larger than the sum of its proper divisors (13751).

20578069 is a wasteful number, since it uses less digits than its factorization.

20578069 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13750.

The product of its (nonzero) digits is 30240, while the sum is 37.

The square root of 20578069 is about 4536.3056554866. The cubic root of 20578069 is about 274.0321636280.

The spelling of 20578069 in words is "twenty million, five hundred seventy-eight thousand, sixty-nine".