211557025 has 9 divisors (see below), whose sum is σ = 262420921. Its totient is φ = 169187440.

The previous prime is 211557019. The next prime is 211557037. The reversal of 211557025 is 520755112.

The square root of 211557025 is 14545.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 15108769 + 196448256 = 3887^2 + 14016^2 .

It is not a de Polignac number, because 211557025 - 2⁷ = 211556897 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 211556984 and 211557002.

It is an unprimeable number.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 71271 + ... + 74179.

Almost surely, 2^211557025 is an apocalyptic number.

211557025 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

211557025 is the 14545-th square number.

211557025 is the 7273-rd centered octagonal number.

It is an amenable number.

211557025 is a deficient number, since it is larger than the sum of its proper divisors (50863896).

211557025 is an frugal number, since it uses more digits than its factorization.

211557025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5828 (or 2914 counting only the distinct ones).

The product of its (nonzero) digits is 3500, while the sum is 28.

The cubic root of 211557025 is about 595.8576009590.

The spelling of 211557025 in words is "two hundred eleven million, five hundred fifty-seven thousand, twenty-five".