61857739 has 2 divisors, whose sum is σ = 61857740. Its totient is φ = 61857738.

The previous prime is 61857703. The next prime is 61857751. The reversal of 61857739 is 93775816.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 61857739 - 2⁹ = 61857227 is a prime.

It is not a weakly prime, because it can be changed into another prime (61857799) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30928869 + 30928870.

It is an arithmetic number, because the mean of its divisors is an integer number (30928870).

Almost surely, 2^61857739 is an apocalyptic number.

61857739 is a deficient number, since it is larger than the sum of its proper divisors (1).

61857739 is an equidigital number, since it uses as much as digits as its factorization.

61857739 is an evil number, because the sum of its binary digits is even.

The product of its digits is 317520, while the sum is 46.

The square root of 61857739 is about 7864.9691035630. The cubic root of 61857739 is about 395.4862121421.

It can be divided in two parts, 6185 and 7739, that added together give a square (13924 = 118²).

The spelling of 61857739 in words is "sixty-one million, eight hundred fifty-seven thousand, seven hundred thirty-nine".