61881439 has 2 divisors, whose sum is σ = 61881440. Its totient is φ = 61881438.

The previous prime is 61881437. The next prime is 61881451. The reversal of 61881439 is 93418816.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 61881439 - 2¹ = 61881437 is a prime.

Together with 61881437, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61881437) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30940719 + 30940720.

It is an arithmetic number, because the mean of its divisors is an integer number (30940720).

Almost surely, 2^61881439 is an apocalyptic number.

61881439 is a deficient number, since it is larger than the sum of its proper divisors (1).

61881439 is an equidigital number, since it uses as much as digits as its factorization.

61881439 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 41472, while the sum is 40.

The square root of 61881439 is about 7866.4756403360. The cubic root of 61881439 is about 395.5367141842.

The spelling of 61881439 in words is "sixty-one million, eight hundred eighty-one thousand, four hundred thirty-nine".