20530731 has 8 divisors (see below), whose sum is σ = 29480080. Its totient is φ = 12634272.

The previous prime is 20530723. The next prime is 20530759. The reversal of 20530731 is 13703502.

It is a happy number.

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

It is not a de Polignac number, because 20530731 - 2³ = 20530723 is a prime.

It is a super-2 number, since 2×20530731² = 843021830788722, 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 = 20530698 and 20530707.

It is not an unprimeable number, because it can be changed into a prime (20530771) 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, 263176 + ... + 263253.

It is an arithmetic number, because the mean of its divisors is an integer number (3685010).

Almost surely, 2^20530731 is an apocalyptic number.

20530731 is a deficient number, since it is larger than the sum of its proper divisors (8949349).

20530731 is a wasteful number, since it uses less digits than its factorization.

20530731 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 526445.

The product of its (nonzero) digits is 630, while the sum is 21.

The square root of 20530731 is about 4531.0849694085. The cubic root of 20530731 is about 273.8218734987.

The spelling of 20530731 in words is "twenty million, five hundred thirty thousand, seven hundred thirty-one".