20405075523 has 16 divisors (see below), whose sum is σ = 31173392640. Its totient is φ = 11630064096.

The previous prime is 20405075461. The next prime is 20405075543. The reversal of 20405075523 is 32557050402.

It is not a de Polignac number, because 20405075523 - 2²² = 20400881219 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20405075543) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1240765 + ... + 1257102.

It is an arithmetic number, because the mean of its divisors is an integer number (1948337040).

Almost surely, 2^20405075523 is an apocalyptic number.

20405075523 is a deficient number, since it is larger than the sum of its proper divisors (10768317117).

20405075523 is a wasteful number, since it uses less digits than its factorization.

20405075523 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2498266.

The product of its (nonzero) digits is 42000, while the sum is 33.

The spelling of 20405075523 in words is "twenty billion, four hundred five million, seventy-five thousand, five hundred twenty-three".