61681751 has 2 divisors, whose sum is σ = 61681752. Its totient is φ = 61681750.

The previous prime is 61681721. The next prime is 61681777. The reversal of 61681751 is 15718616.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 61681751 - 2⁶ = 61681687 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61681721) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30840875 + 30840876.

It is an arithmetic number, because the mean of its divisors is an integer number (30840876).

Almost surely, 2^61681751 is an apocalyptic number.

61681751 is a deficient number, since it is larger than the sum of its proper divisors (1).

61681751 is an equidigital number, since it uses as much as digits as its factorization.

61681751 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10080, while the sum is 35.

The square root of 61681751 is about 7853.7730423027. The cubic root of 61681751 is about 395.1107973114.

The spelling of 61681751 in words is "sixty-one million, six hundred eighty-one thousand, seven hundred fifty-one".