61315660 has 144 divisors (see below), whose sum is σ = 163749600. Its totient is φ = 19160064.

The previous prime is 61315643. The next prime is 61315663. The reversal of 61315660 is 6651316.

It is a super-2 number, since 2×61315660² = 7519220322471200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is not an unprimeable number, because it can be changed into a prime (61315663) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 688896 + ... + 688984.

It is an arithmetic number, because the mean of its divisors is an integer number (1137150).

Almost surely, 2^61315660 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61315660, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (81874800).

61315660 is an abundant number, since it is smaller than the sum of its proper divisors (102433940).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

61315660 is a wasteful number, since it uses less digits than its factorization.

61315660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 168 (or 159 counting only the distinct ones).

The product of its (nonzero) digits is 3240, while the sum is 28.

The square root of 61315660 is about 7830.4316611538. The cubic root of 61315660 is about 394.3275639209.

Adding to 61315660 its reverse (6651316), we get a palindrome (67966976).

The spelling of 61315660 in words is "sixty-one million, three hundred fifteen thousand, six hundred sixty".