820838155 has 16 divisors (see below), whose sum is σ = 1013753664. Its totient is φ = 637580160.

The previous prime is 820838147. The next prime is 820838159. The reversal of 820838155 is 551838028.

It is not a de Polignac number, because 820838155 - 2³ = 820838147 is a prime.

It is a super-5 number, since 5×820838155⁵ (a number of 46 digits) contains 55555 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (820838159) 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, 88645 + ... + 97465.

It is an arithmetic number, because the mean of its divisors is an integer number (63359604).

Almost surely, 2^820838155 is an apocalyptic number.

820838155 is a deficient number, since it is larger than the sum of its proper divisors (192915509).

820838155 is a wasteful number, since it uses less digits than its factorization.

820838155 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9366.

The product of its (nonzero) digits is 76800, while the sum is 40.

The square root of 820838155 is about 28650.2732098666. The cubic root of 820838155 is about 936.3089581250.

The spelling of 820838155 in words is "eight hundred twenty million, eight hundred thirty-eight thousand, one hundred fifty-five".