52821557 has 4 divisors (see below), whose sum is σ = 54643020. Its totient is φ = 51000096.

The previous prime is 52821553. The next prime is 52821563. The reversal of 52821557 is 75512825.

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 15928081 + 36893476 = 3991^2 + 6074^2 .

It is not a de Polignac number, because 52821557 - 2² = 52821553 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (52821553) 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, 910688 + ... + 910745.

It is an arithmetic number, because the mean of its divisors is an integer number (13660755).

Almost surely, 2^52821557 is an apocalyptic number.

It is an amenable number.

52821557 is a deficient number, since it is larger than the sum of its proper divisors (1821463).

52821557 is a wasteful number, since it uses less digits than its factorization.

52821557 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1821462.

The product of its digits is 28000, while the sum is 35.

The square root of 52821557 is about 7267.8440407042. The cubic root of 52821557 is about 375.2065398522.

The spelling of 52821557 in words is "fifty-two million, eight hundred twenty-one thousand, five hundred fifty-seven".