825669749 has 4 divisors (see below), whose sum is σ = 829861164. Its totient is φ = 821478336.

The previous prime is 825669707. The next prime is 825669781. The reversal of 825669749 is 947966528.

It is a happy number.

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 559653649 + 266016100 = 23657^2 + 16310^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-825669749 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 825669694 and 825669703.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (825669349) 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, 2095412 + ... + 2095805.

It is an arithmetic number, because the mean of its divisors is an integer number (207465291).

Almost surely, 2^825669749 is an apocalyptic number.

It is an amenable number.

825669749 is a deficient number, since it is larger than the sum of its proper divisors (4191415).

825669749 is a wasteful number, since it uses less digits than its factorization.

825669749 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4191414.

The product of its digits is 6531840, while the sum is 56.

The square root of 825669749 is about 28734.4697010402. The cubic root of 825669749 is about 938.1424570302.

The spelling of 825669749 in words is "eight hundred twenty-five million, six hundred sixty-nine thousand, seven hundred forty-nine".