820097409 has 16 divisors (see below), whose sum is σ = 1131923520. Its totient is φ = 527526720.

The previous prime is 820097401. The next prime is 820097413. The reversal of 820097409 is 904790028.

It is not a de Polignac number, because 820097409 - 2³ = 820097401 is a prime.

It is not an unprimeable number, because it can be changed into a prime (820097401) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 212719 + ... + 216539.

It is an arithmetic number, because the mean of its divisors is an integer number (70745220).

Almost surely, 2^820097409 is an apocalyptic number.

It is an amenable number.

820097409 is a deficient number, since it is larger than the sum of its proper divisors (311826111).

820097409 is a wasteful number, since it uses less digits than its factorization.

820097409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6320.

The product of its (nonzero) digits is 36288, while the sum is 39.

The square root of 820097409 is about 28637.3429109616. The cubic root of 820097409 is about 936.0272233937.

The spelling of 820097409 in words is "eight hundred twenty million, ninety-seven thousand, four hundred nine".