820081445 has 32 divisors (see below), whose sum is σ = 1090672128. Its totient is φ = 588791808.

The previous prime is 820081429. The next prime is 820081463. The reversal of 820081445 is 544180028.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 820081445 - 2⁴ = 820081429 is a prime.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1127672 + ... + 1128398.

It is an arithmetic number, because the mean of its divisors is an integer number (34083504).

Almost surely, 2^820081445 is an apocalyptic number.

820081445 is a gapful number since it is divisible by the number (85) formed by its first and last digit.

It is an amenable number.

820081445 is a deficient number, since it is larger than the sum of its proper divisors (270590683).

820081445 is a wasteful number, since it uses less digits than its factorization.

820081445 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1349.

The product of its (nonzero) digits is 10240, while the sum is 32.

The square root of 820081445 is about 28637.0641826288. The cubic root of 820081445 is about 936.0211497918.

The spelling of 820081445 in words is "eight hundred twenty million, eighty-one thousand, four hundred forty-five".