820156897 has 4 divisors (see below), whose sum is σ = 937322176. Its totient is φ = 702991620.

The previous prime is 820156867. The next prime is 820156903. The reversal of 820156897 is 798651028.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 820156897 - 2⁷ = 820156769 is a prime.

It is not an unprimeable number, because it can be changed into a prime (820156867) 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, 58582629 + ... + 58582642.

It is an arithmetic number, because the mean of its divisors is an integer number (234330544).

Almost surely, 2^820156897 is an apocalyptic number.

It is an amenable number.

820156897 is a deficient number, since it is larger than the sum of its proper divisors (117165279).

820156897 is a wasteful number, since it uses less digits than its factorization.

820156897 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 117165278.

The product of its (nonzero) digits is 241920, while the sum is 46.

The square root of 820156897 is about 28638.3815359737. The cubic root of 820156897 is about 936.0498552748.

The spelling of 820156897 in words is "eight hundred twenty million, one hundred fifty-six thousand, eight hundred ninety-seven".