20405825507 has 4 divisors (see below), whose sum is σ = 20466377256. Its totient is φ = 20345273760.

The previous prime is 20405825471. The next prime is 20405825513. The reversal of 20405825507 is 70552850402.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 70552850402 = 2 ⋅35276425201.

It is a cyclic number.

It is not a de Polignac number, because 20405825507 - 2²⁴ = 20389048291 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20405825537) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 30275369 + ... + 30276042.

It is an arithmetic number, because the mean of its divisors is an integer number (5116594314).

Almost surely, 2^20405825507 is an apocalyptic number.

20405825507 is a deficient number, since it is larger than the sum of its proper divisors (60551749).

20405825507 is an equidigital number, since it uses as much as digits as its factorization.

20405825507 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60551748.

The product of its (nonzero) digits is 112000, while the sum is 38.

The spelling of 20405825507 in words is "twenty billion, four hundred five million, eight hundred twenty-five thousand, five hundred seven".