820525553 has 4 divisors (see below), whose sum is σ = 868791780. Its totient is φ = 772259328.

The previous prime is 820525543. The next prime is 820525561. The reversal of 820525553 is 355525028.

820525553 = T₅₆₄₇ + T₅₆₄₈ + ... + T₅₆₉₇.

820525553 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 524272609 + 296252944 = 22897^2 + 17212^2 .

It is a cyclic number.

It is not a de Polignac number, because 820525553 - 2⁸ = 820525297 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (820525543) 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, 24133088 + ... + 24133121.

It is an arithmetic number, because the mean of its divisors is an integer number (217197945).

Almost surely, 2^820525553 is an apocalyptic number.

It is an amenable number.

820525553 is a deficient number, since it is larger than the sum of its proper divisors (48266227).

820525553 is a wasteful number, since it uses less digits than its factorization.

820525553 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48266226.

The product of its (nonzero) digits is 60000, while the sum is 35.

The square root of 820525553 is about 28644.8172100993. The cubic root of 820525553 is about 936.1900840146.

The spelling of 820525553 in words is "eight hundred twenty million, five hundred twenty-five thousand, five hundred fifty-three".