820457739 has 24 divisors (see below), whose sum is σ = 1214653440. Its totient is φ = 533503152.

The previous prime is 820457669. The next prime is 820457741. The reversal of 820457739 is 937754028.

It is not a de Polignac number, because 820457739 - 2²⁴ = 803680523 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 820457694 and 820457703.

It is not an unprimeable number, because it can be changed into a prime (820457789) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 52062 + ... + 65964.

It is an arithmetic number, because the mean of its divisors is an integer number (50610560).

Almost surely, 2^820457739 is an apocalyptic number.

820457739 is a deficient number, since it is larger than the sum of its proper divisors (394195701).

820457739 is a wasteful number, since it uses less digits than its factorization.

820457739 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14071 (or 14068 counting only the distinct ones).

The product of its (nonzero) digits is 423360, while the sum is 45.

The square root of 820457739 is about 28643.6334811071. The cubic root of 820457739 is about 936.1642921941.

The spelling of 820457739 in words is "eight hundred twenty million, four hundred fifty-seven thousand, seven hundred thirty-nine".