20731347 has 48 divisors (see below), whose sum is σ = 39049920. Its totient is φ = 10285056.

The previous prime is 20731339. The next prime is 20731351. The reversal of 20731347 is 74313702.

It is not a de Polignac number, because 20731347 - 2³ = 20731339 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20731347.

It is not an unprimeable number, because it can be changed into a prime (20731307) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 13179 + ... + 14667.

It is an arithmetic number, because the mean of its divisors is an integer number (813540).

Almost surely, 2^20731347 is an apocalyptic number.

20731347 is a deficient number, since it is larger than the sum of its proper divisors (18318573).

20731347 is a wasteful number, since it uses less digits than its factorization.

20731347 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1532 (or 1529 counting only the distinct ones).

The product of its (nonzero) digits is 3528, while the sum is 27.

The square root of 20731347 is about 4553.1688964940. The cubic root of 20731347 is about 274.7108674650.

The spelling of 20731347 in words is "twenty million, seven hundred thirty-one thousand, three hundred forty-seven".