61868531 has 2 divisors, whose sum is σ = 61868532. Its totient is φ = 61868530.

The previous prime is 61868507. The next prime is 61868533. The reversal of 61868531 is 13586816.

It is a happy number.

61868531 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 61868531 - 2¹⁸ = 61606387 is a prime.

It is a super-2 number, since 2×61868531² = 7655430256195922, which contains 22 as substring.

Together with 61868533, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (61868533) 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 as a sum of consecutive naturals, namely, 30934265 + 30934266.

It is an arithmetic number, because the mean of its divisors is an integer number (30934266).

Almost surely, 2^61868531 is an apocalyptic number.

61868531 is a deficient number, since it is larger than the sum of its proper divisors (1).

61868531 is an equidigital number, since it uses as much as digits as its factorization.

61868531 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 34560, while the sum is 38.

The square root of 61868531 is about 7865.6551538953. The cubic root of 61868531 is about 395.5092102831.

The spelling of 61868531 in words is "sixty-one million, eight hundred sixty-eight thousand, five hundred thirty-one".