61172780 has 24 divisors (see below), whose sum is σ = 135224880. Its totient is φ = 23181120.

The previous prime is 61172777. The next prime is 61172807. The reversal of 61172780 is 8727116.

61172780 is digitally balanced in base 2 and base 9, because in such bases it contains all the possibile digits an equal number of times.

61172780 is strictly pandigital in base 9.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 80111 + ... + 80870.

It is an arithmetic number, because the mean of its divisors is an integer number (5634370).

Almost surely, 2^61172780 is an apocalyptic number.

It is an amenable number.

61172780 is an abundant number, since it is smaller than the sum of its proper divisors (74052100).

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

61172780 is a wasteful number, since it uses less digits than its factorization.

61172780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 161009 (or 161007 counting only the distinct ones).

The product of its (nonzero) digits is 4704, while the sum is 32.

The square root of 61172780 is about 7821.3029605047. The cubic root of 61172780 is about 394.0210335168.

Adding to 61172780 its reverse (8727116), we get a palindrome (69899896).

The spelling of 61172780 in words is "sixty-one million, one hundred seventy-two thousand, seven hundred eighty".