61689031 has 4 divisors (see below), whose sum is σ = 62265672. Its totient is φ = 61112392.

The previous prime is 61688987. The next prime is 61689037. The reversal of 61689031 is 13098616.

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 61689031 - 2⁹ = 61688519 is a prime.

It is a super-2 number, since 2×61689031² = 7611073091437922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61689037) 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, 288160 + ... + 288373.

It is an arithmetic number, because the mean of its divisors is an integer number (15566418).

Almost surely, 2^61689031 is an apocalyptic number.

61689031 is a deficient number, since it is larger than the sum of its proper divisors (576641).

61689031 is a wasteful number, since it uses less digits than its factorization.

61689031 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 576640.

The product of its (nonzero) digits is 7776, while the sum is 34.

The square root of 61689031 is about 7854.2365001316. The cubic root of 61689031 is about 395.1263410414.

The spelling of 61689031 in words is "sixty-one million, six hundred eighty-nine thousand, thirty-one".