61313531 has 4 divisors (see below), whose sum is σ = 61908912. Its totient is φ = 60718152.

The previous prime is 61313519. The next prime is 61313537. The reversal of 61313531 is 13531316.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 61313531 - 2⁶ = 61313467 is a prime.

It is a super-2 number, since 2×61313531² = 7518698167375922, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 61313497 and 61313506.

It is not an unprimeable number, because it can be changed into a prime (61313537) 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 3 ways as a sum of consecutive naturals, for example, 297536 + ... + 297741.

It is an arithmetic number, because the mean of its divisors is an integer number (15477228).

Almost surely, 2^61313531 is an apocalyptic number.

61313531 is a deficient number, since it is larger than the sum of its proper divisors (595381).

61313531 is a wasteful number, since it uses less digits than its factorization.

61313531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 595380.

The product of its digits is 810, while the sum is 23.

The square root of 61313531 is about 7830.2957159995. The cubic root of 61313531 is about 394.3229999259.

Adding to 61313531 its reverse (13531316), we get a palindrome (74844847).

The spelling of 61313531 in words is "sixty-one million, three hundred thirteen thousand, five hundred thirty-one".