61688971 has 4 divisors (see below), whose sum is σ = 65317752. Its totient is φ = 58060192.

The previous prime is 61688947. The next prime is 61688981. The reversal of 61688971 is 17988616.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 61688971 - 2¹¹ = 61686923 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61688941) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1814365 + ... + 1814398.

It is an arithmetic number, because the mean of its divisors is an integer number (16329438).

Almost surely, 2^61688971 is an apocalyptic number.

61688971 is a deficient number, since it is larger than the sum of its proper divisors (3628781).

61688971 is a wasteful number, since it uses less digits than its factorization.

61688971 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3628780.

The product of its digits is 145152, while the sum is 46.

The square root of 61688971 is about 7854.2326805360. The cubic root of 61688971 is about 395.1262129387.

The spelling of 61688971 in words is "sixty-one million, six hundred eighty-eight thousand, nine hundred seventy-one".