20712869 has 4 divisors (see below), whose sum is σ = 21803040. Its totient is φ = 19622700.

The previous prime is 20712847. The next prime is 20712871. The reversal of 20712869 is 96821702.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 96821702 = 2 ⋅48410851.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20712869 is a prime.

It is a super-2 number, since 2×20712869² = 858045884422322, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20712829) 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, 545057 + ... + 545094.

It is an arithmetic number, because the mean of its divisors is an integer number (5450760).

Almost surely, 2^20712869 is an apocalyptic number.

It is an amenable number.

20712869 is a deficient number, since it is larger than the sum of its proper divisors (1090171).

20712869 is a wasteful number, since it uses less digits than its factorization.

20712869 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1090170.

The product of its (nonzero) digits is 12096, while the sum is 35.

The square root of 20712869 is about 4551.1393079096. The cubic root of 20712869 is about 274.6292259412.

The spelling of 20712869 in words is "twenty million, seven hundred twelve thousand, eight hundred sixty-nine".