61661517 has 8 divisors (see below), whose sum is σ = 86542560. Its totient is φ = 38944080.

The previous prime is 61661513. The next prime is 61661519. The reversal of 61661517 is 71516616.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 61661517 - 2² = 61661513 is a prime.

It is a super-3 number, since 3×61661517³ (a number of 24 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61661513) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 540834 + ... + 540947.

It is an arithmetic number, because the mean of its divisors is an integer number (10817820).

Almost surely, 2^61661517 is an apocalyptic number.

It is an amenable number.

61661517 is a deficient number, since it is larger than the sum of its proper divisors (24881043).

61661517 is a wasteful number, since it uses less digits than its factorization.

61661517 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1081803.

The product of its digits is 7560, while the sum is 33.

The square root of 61661517 is about 7852.4847659833. The cubic root of 61661517 is about 395.0675887119.

The spelling of 61661517 in words is "sixty-one million, six hundred sixty-one thousand, five hundred seventeen".