820209823525 has 24 divisors (see below), whose sum is σ = 1061336534400. Its totient is φ = 627605499840.

The previous prime is 820209823519. The next prime is 820209823567. The reversal of 820209823525 is 525328902028.

It is not a de Polignac number, because 820209823525 - 2¹⁹ = 820209299237 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 20190384 + ... + 20230966.

It is an arithmetic number, because the mean of its divisors is an integer number (44222355600).

Almost surely, 2^820209823525 is an apocalyptic number.

It is an amenable number.

820209823525 is a deficient number, since it is larger than the sum of its proper divisors (241126710875).

820209823525 is a wasteful number, since it uses less digits than its factorization.

820209823525 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 75765 (or 75760 counting only the distinct ones).

The product of its (nonzero) digits is 691200, while the sum is 46.

The spelling of 820209823525 in words is "eight hundred twenty billion, two hundred nine million, eight hundred twenty-three thousand, five hundred twenty-five".