61661501 has 12 divisors (see below), whose sum is σ = 68022240. Its totient is φ = 55433280.

The previous prime is 61661491. The next prime is 61661503. The reversal of 61661501 is 10516616.

It is not a de Polignac number, because 61661501 - 2²² = 57467197 is a prime.

It is a super-3 number, since 3×61661501³ (a number of 24 digits) contains 333 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61661503) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 140240 + ... + 140678.

It is an arithmetic number, because the mean of its divisors is an integer number (5668520).

Almost surely, 2^61661501 is an apocalyptic number.

It is an amenable number.

61661501 is a deficient number, since it is larger than the sum of its proper divisors (6360739).

61661501 is a wasteful number, since it uses less digits than its factorization.

61661501 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 676 (or 563 counting only the distinct ones).

The product of its (nonzero) digits is 1080, while the sum is 26.

The square root of 61661501 is about 7852.4837471974. The cubic root of 61661501 is about 395.0675545411.

It can be divided in two parts, 6166 and 1501, that added together give a palindrome (7667).

The spelling of 61661501 in words is "sixty-one million, six hundred sixty-one thousand, five hundred one".