61531263 has 12 divisors (see below), whose sum is σ = 89695320. Its totient is φ = 40643856.

The previous prime is 61531247. The next prime is 61531289. The reversal of 61531263 is 36213516.

It is not a de Polignac number, because 61531263 - 2⁴ = 61531247 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61531213) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 30381 + ... + 32342.

It is an arithmetic number, because the mean of its divisors is an integer number (7474610).

Almost surely, 2^61531263 is an apocalyptic number.

61531263 is a deficient number, since it is larger than the sum of its proper divisors (28164057).

61531263 is a wasteful number, since it uses less digits than its factorization.

61531263 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 62838 (or 62835 counting only the distinct ones).

The product of its digits is 3240, while the sum is 27.

The square root of 61531263 is about 7844.1865735078. The cubic root of 61531263 is about 394.7892118953.

Adding to 61531263 its reverse (36213516), we get a palindrome (97744779).

It can be divided in two parts, 615 and 31263, that added together give a triangular number (31878 = T₂₅₂).

The spelling of 61531263 in words is "sixty-one million, five hundred thirty-one thousand, two hundred sixty-three".