61561472 has 64 divisors (see below), whose sum is σ = 141527040. Its totient is φ = 26127360.

The previous prime is 61561447. The next prime is 61561477. The reversal of 61561472 is 27416516.

It is a tau number, because it is divible by the number of its divisors (64).

It is a Harshad number since it is a multiple of its sum of digits (32).

It is not an unprimeable number, because it can be changed into a prime (61561477) 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, 113522 + ... + 114062.

It is an arithmetic number, because the mean of its divisors is an integer number (2211360).

Almost surely, 2^61561472 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 61561472, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (70763520).

61561472 is an abundant number, since it is smaller than the sum of its proper divisors (79965568).

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

61561472 is a wasteful number, since it uses less digits than its factorization.

61561472 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 689 (or 677 counting only the distinct ones).

The product of its digits is 10080, while the sum is 32.

The square root of 61561472 is about 7846.1119033570. Note that the first 3 decimals coincide. The cubic root of 61561472 is about 394.8538090638.

Adding to 61561472 its reverse (27416516), we get a palindrome (88977988).

The spelling of 61561472 in words is "sixty-one million, five hundred sixty-one thousand, four hundred seventy-two".