215198571025 has 9 divisors (see below), whose sum is σ = 266849104251. Its totient is φ = 172157001240.

The previous prime is 215198570987. The next prime is 215198571031. The reversal of 215198571025 is 520175891512.

It is a happy number.

The square root of 215198571025 is 463895.

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

It can be written as a sum of positive squares in only one way, i.e., 77471485569 + 137727085456 = 278337^2 + 371116^2 .

It is not a de Polignac number, because 215198571025 - 2²⁵ = 215165016593 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 2273086 + ... + 2365864.

Almost surely, 2^215198571025 is an apocalyptic number.

215198571025 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

215198571025 is the 463895-th square number.

215198571025 is the 231948-th centered octagonal number.

It is an amenable number.

215198571025 is a deficient number, since it is larger than the sum of its proper divisors (51650533226).

215198571025 is an frugal number, since it uses more digits than its factorization.

215198571025 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 185568 (or 92784 counting only the distinct ones).

The product of its (nonzero) digits is 252000, while the sum is 46.

The spelling of 215198571025 in words is "two hundred fifteen billion, one hundred ninety-eight million, five hundred seventy-one thousand, twenty-five".