191454378025 has 9 divisors (see below), whose sum is σ = 237406141623. Its totient is φ = 153161752200.

The previous prime is 191454377969. The next prime is 191454378041. The reversal of 191454378025 is 520873454191.

It is a happy number.

The square root of 191454378025 is 437555.

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., 68923576089 + 122530801936 = 262533^2 + 350044^2 .

It is not a de Polignac number, because 191454378025 - 2¹¹ = 191454375977 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 191454378025.

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, 2144020 + ... + 2231530.

Almost surely, 2^191454378025 is an apocalyptic number.

191454378025 is the 437555-th square number.

191454378025 is the 218778-th centered octagonal number.

It is an amenable number.

191454378025 is a deficient number, since it is larger than the sum of its proper divisors (45951763598).

191454378025 is an frugal number, since it uses more digits than its factorization.

191454378025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 175032 (or 87516 counting only the distinct ones).

The product of its (nonzero) digits is 1209600, while the sum is 49.

Multiplying 191454378025 by its sum of digits (49), we get a square (9381264523225 = 3062885²).

The spelling of 191454378025 in words is "one hundred ninety-one billion, four hundred fifty-four million, three hundred seventy-eight thousand, twenty-five".