61681719 has 16 divisors (see below), whose sum is σ = 91630080. Its totient is φ = 36586560.

The previous prime is 61681709. The next prime is 61681721. The reversal of 61681719 is 91718616.

It is not a de Polignac number, because 61681719 - 2⁵ = 61681687 is a prime.

It is a super-2 number, since 2×61681719² = 7609268917589922, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61681709) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 18334 + ... + 21435.

It is an arithmetic number, because the mean of its divisors is an integer number (5726880).

Almost surely, 2^61681719 is an apocalyptic number.

61681719 is a deficient number, since it is larger than the sum of its proper divisors (29948361).

61681719 is a wasteful number, since it uses less digits than its factorization.

61681719 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39830.

The product of its digits is 18144, while the sum is 39.

The square root of 61681719 is about 7853.7710050650. The cubic root of 61681719 is about 395.1107289846.

It can be divided in two parts, 6168 and 1719, that added together give a palindrome (7887).

The spelling of 61681719 in words is "sixty-one million, six hundred eighty-one thousand, seven hundred nineteen".