815765620403 has 4 divisors (see below), whose sum is σ = 842080640448. Its totient is φ = 789450600360.

The previous prime is 815765620393. The next prime is 815765620421. The reversal of 815765620403 is 304026567518.

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

It is a cyclic number.

It is not a de Polignac number, because 815765620403 - 2⁴ = 815765620387 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (815765620493) 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, 13157509976 + ... + 13157510037.

It is an arithmetic number, because the mean of its divisors is an integer number (210520160112).

Almost surely, 2^815765620403 is an apocalyptic number.

815765620403 is a deficient number, since it is larger than the sum of its proper divisors (26315020045).

815765620403 is a wasteful number, since it uses less digits than its factorization.

815765620403 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26315020044.

The product of its (nonzero) digits is 1209600, while the sum is 47.

The spelling of 815765620403 in words is "eight hundred fifteen billion, seven hundred sixty-five million, six hundred twenty thousand, four hundred three".