61631749 has 4 divisors (see below), whose sum is σ = 65257164. Its totient is φ = 58006336.

The previous prime is 61631747. The next prime is 61631819. The reversal of 61631749 is 94713616.

61631749 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 28281124 + 33350625 = 5318^2 + 5775^2 .

It is a cyclic number.

It is not a de Polignac number, because 61631749 - 2¹ = 61631747 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61631741) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1812682 + ... + 1812715.

It is an arithmetic number, because the mean of its divisors is an integer number (16314291).

Almost surely, 2^61631749 is an apocalyptic number.

It is an amenable number.

61631749 is a deficient number, since it is larger than the sum of its proper divisors (3625415).

61631749 is a wasteful number, since it uses less digits than its factorization.

61631749 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3625414.

The product of its digits is 27216, while the sum is 37.

The square root of 61631749 is about 7850.5890861769. The cubic root of 61631749 is about 395.0040035913.

The spelling of 61631749 in words is "sixty-one million, six hundred thirty-one thousand, seven hundred forty-nine".