20497507 has 4 divisors (see below), whose sum is σ = 20549536. Its totient is φ = 20445480.

The previous prime is 20497481. The next prime is 20497553. The reversal of 20497507 is 70579402.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20497507 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20497567) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 25419 + ... + 26212.

It is an arithmetic number, because the mean of its divisors is an integer number (5137384).

Almost surely, 2^20497507 is an apocalyptic number.

20497507 is a deficient number, since it is larger than the sum of its proper divisors (52029).

20497507 is an equidigital number, since it uses as much as digits as its factorization.

20497507 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52028.

The product of its (nonzero) digits is 17640, while the sum is 34.

The square root of 20497507 is about 4527.4172549037. The cubic root of 20497507 is about 273.6740890274.

The spelling of 20497507 in words is "twenty million, four hundred ninety-seven thousand, five hundred seven".