20731407 has 8 divisors (see below), whose sum is σ = 27715584. Its totient is φ = 13784088.

The previous prime is 20731397. The next prime is 20731409. The reversal of 20731407 is 70413702.

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

It is not a de Polignac number, because 20731407 - 2⁴ = 20731391 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20731409) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7873 + ... + 10170.

It is an arithmetic number, because the mean of its divisors is an integer number (3464448).

Almost surely, 2^20731407 is an apocalyptic number.

20731407 is a deficient number, since it is larger than the sum of its proper divisors (6984177).

20731407 is a wasteful number, since it uses less digits than its factorization.

20731407 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18429.

The product of its (nonzero) digits is 1176, while the sum is 24.

The square root of 20731407 is about 4553.1754853069. The cubic root of 20731407 is about 274.7111324846.

The spelling of 20731407 in words is "twenty million, seven hundred thirty-one thousand, four hundred seven".