61285531 has 2 divisors, whose sum is σ = 61285532. Its totient is φ = 61285530.

The previous prime is 61285519. The next prime is 61285537. The reversal of 61285531 is 13558216.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 61285531 - 2¹³ = 61277339 is a prime.

It is a super-2 number, since 2×61285531² = 7511832619903922, which contains 22 as substring.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 61285493 and 61285502.

It is not a weakly prime, because it can be changed into another prime (61285537) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30642765 + 30642766.

It is an arithmetic number, because the mean of its divisors is an integer number (30642766).

Almost surely, 2^61285531 is an apocalyptic number.

61285531 is a deficient number, since it is larger than the sum of its proper divisors (1).

61285531 is an equidigital number, since it uses as much as digits as its factorization.

61285531 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7200, while the sum is 31.

The square root of 61285531 is about 7828.5075844633. The cubic root of 61285531 is about 394.2629657325.

It can be divided in two parts, 61285 and 531, that added together give a palindrome (61816).

The spelling of 61285531 in words is "sixty-one million, two hundred eighty-five thousand, five hundred thirty-one".