20513907 has 24 divisors (see below), whose sum is σ = 31228704. Its totient is φ = 12950784.

The previous prime is 20513903. The next prime is 20513921. The reversal of 20513907 is 70931502.

It is not a de Polignac number, because 20513907 - 2² = 20513903 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20513903) 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 23 ways as a sum of consecutive naturals, for example, 22953 + ... + 23829.

It is an arithmetic number, because the mean of its divisors is an integer number (1301196).

Almost surely, 2^20513907 is an apocalyptic number.

20513907 is a deficient number, since it is larger than the sum of its proper divisors (10714797).

20513907 is a wasteful number, since it uses less digits than its factorization.

20513907 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1019 (or 1016 counting only the distinct ones).

The product of its (nonzero) digits is 1890, while the sum is 27.

The square root of 20513907 is about 4529.2280799271. The cubic root of 20513907 is about 273.7470582032.

The spelling of 20513907 in words is "twenty million, five hundred thirteen thousand, nine hundred seven".