2158445797225 has 27 divisors (see below), whose sum is σ = 2698262811319. Its totient is φ = 1712811323600.

The previous prime is 2158445797199. The next prime is 2158445797243. The reversal of 2158445797225 is 5227975448512.

The square root of 2158445797225 is 1469165.

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., 777040487001 + 1381405310224 = 881499^2 + 1175332^2 .

It is not a de Polignac number, because 2158445797225 - 2⁹ = 2158445796713 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 962301954 + ... + 962304196.

Almost surely, 2^{2158445797225} is an apocalyptic number.

2158445797225 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

2158445797225 is the 1469165-th square number.

2158445797225 is the 734583-rd centered octagonal number.

It is an amenable number.

2158445797225 is a deficient number, since it is larger than the sum of its proper divisors (539817014094).

2158445797225 is an frugal number, since it uses more digits than its factorization.

2158445797225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4758 (or 2379 counting only the distinct ones).

The product of its digits is 56448000, while the sum is 61.

The spelling of 2158445797225 in words is "two trillion, one hundred fifty-eight billion, four hundred forty-five million, seven hundred ninety-seven thousand, two hundred twenty-five".