61689605 has 16 divisors (see below), whose sum is σ = 75661824. Its totient is φ = 48271680.

The previous prime is 61689587. The next prime is 61689629. The reversal of 61689605 is 50698616.

It is a de Polignac number, because none of the positive numbers 2^k-61689605 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 67562 + ... + 68468.

It is an arithmetic number, because the mean of its divisors is an integer number (4728864).

Almost surely, 2^61689605 is an apocalyptic number.

61689605 is the 4535-th octagonal number.

It is an amenable number.

61689605 is a deficient number, since it is larger than the sum of its proper divisors (13972219).

61689605 is a wasteful number, since it uses less digits than its factorization.

61689605 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1196.

The product of its (nonzero) digits is 77760, while the sum is 41.

The square root of 61689605 is about 7854.2730408358. The cubic root of 61689605 is about 395.1275665527.

The spelling of 61689605 in words is "sixty-one million, six hundred eighty-nine thousand, six hundred five".