42777725 has 12 divisors (see below), whose sum is σ = 53249940. Its totient is φ = 34089600.

The previous prime is 42777703. The next prime is 42777727. The reversal of 42777725 is 52777724.

It can be written as a sum of positive squares in 6 ways, for example, as 11215801 + 31561924 = 3349^2 + 5618^2 .

It is a de Polignac number, because none of the positive numbers 2^k-42777725 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42777727) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3545 + ... + 9905.

It is an arithmetic number, because the mean of its divisors is an integer number (4437495).

Almost surely, 2^42777725 is an apocalyptic number.

It is an amenable number.

42777725 is a deficient number, since it is larger than the sum of its proper divisors (10472215).

42777725 is a wasteful number, since it uses less digits than its factorization.

42777725 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6640 (or 6635 counting only the distinct ones).

The product of its digits is 192080, while the sum is 41.

The square root of 42777725 is about 6540.4682554080. The cubic root of 42777725 is about 349.7351056902.

Subtracting 42777725 from its reverse (52777724), we obtain a palindrome (9999999).

The spelling of 42777725 in words is "forty-two million, seven hundred seventy-seven thousand, seven hundred twenty-five".