820465397 has 2 divisors, whose sum is σ = 820465398. Its totient is φ = 820465396.

The previous prime is 820465363. The next prime is 820465409. The reversal of 820465397 is 793564028.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 742072081 + 78393316 = 27241^2 + 8854^2 .

It is a cyclic number.

It is not a de Polignac number, because 820465397 - 2²⁰ = 819416821 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (820465297) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 410232698 + 410232699.

It is an arithmetic number, because the mean of its divisors is an integer number (410232699).

Almost surely, 2^820465397 is an apocalyptic number.

It is an amenable number.

820465397 is a deficient number, since it is larger than the sum of its proper divisors (1).

820465397 is an equidigital number, since it uses as much as digits as its factorization.

820465397 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 362880, while the sum is 44.

The square root of 820465397 is about 28643.7671579700. The cubic root of 820465397 is about 936.1672048462.

The spelling of 820465397 in words is "eight hundred twenty million, four hundred sixty-five thousand, three hundred ninety-seven".