61615 has 4 divisors (see below), whose sum is σ = 73944. Its totient is φ = 49288.

The previous prime is 61613. The next prime is 61627. The reversal of 61615 is 51616.

61615 = 109² + 110² + ... + 113².

61615 is nontrivially palindromic in base 11.

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 61615 - 2¹ = 61613 is a prime.

It is a Duffinian number.

61615 is a lucky number.

It is a zygodrome in base 4.

It is a junction number, because it is equal to n+sod(n) for n = 61592 and 61601.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61613) 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, 6157 + ... + 6166.

It is an arithmetic number, because the mean of its divisors is an integer number (18486).

2⁶¹⁶¹⁵ is an apocalyptic number.

61615 is a deficient number, since it is larger than the sum of its proper divisors (12329).

61615 is a wasteful number, since it uses less digits than its factorization.

61615 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12328.

The product of its digits is 180, while the sum is 19.

The square root of 61615 is about 248.2236894416. The cubic root of 61615 is about 39.4968218348.

Subtracting from 61615 its reverse (51616), we obtain a palindrome (9999).

It can be divided in two parts, 61 and 615, that added together give a palindrome (676).

The spelling of 61615 in words is "sixty-one thousand, six hundred fifteen".