820071405 has 16 divisors (see below), whose sum is σ = 1457904960. Its totient is φ = 437371344.

The previous prime is 820071391. The next prime is 820071431. The reversal of 820071405 is 504170028.

It is not a de Polignac number, because 820071405 - 2⁷ = 820071277 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3037167 + ... + 3037436.

It is an arithmetic number, because the mean of its divisors is an integer number (91119060).

Almost surely, 2^820071405 is an apocalyptic number.

It is an amenable number.

820071405 is a deficient number, since it is larger than the sum of its proper divisors (637833555).

820071405 is a wasteful number, since it uses less digits than its factorization.

820071405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6074617 (or 6074611 counting only the distinct ones).

The product of its (nonzero) digits is 2240, while the sum is 27.

The square root of 820071405 is about 28636.8888847933. Note that the first 5 decimals coincide. The cubic root of 820071405 is about 936.0173299717.

The spelling of 820071405 in words is "eight hundred twenty million, seventy-one thousand, four hundred five".