61780000 has 60 divisors (see below), whose sum is σ = 152037270. Its totient is φ = 24704000.

The previous prime is 61779997. The next prime is 61780003. The reversal of 61780000 is 8716.

It is an interprime number because it is at equal distance from previous prime (61779997) and next prime (61780003).

It can be written as a sum of positive squares in 5 ways, for example, as 7551504 + 54228496 = 2748^2 + 7364^2 .

It is not an unprimeable number, because it can be changed into a prime (61780003) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 18456 + ... + 21544.

Almost surely, 2^61780000 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 61780000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (76018635).

61780000 is an abundant number, since it is smaller than the sum of its proper divisors (90257270).

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

61780000 is an equidigital number, since it uses as much as digits as its factorization.

61780000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3119 (or 3096 counting only the distinct ones).

The product of its (nonzero) digits is 336, while the sum is 22.

The square root of 61780000 is about 7860.0254452514. The cubic root of 61780000 is about 395.3204684454.

Adding to 61780000 its reverse (8716), we get a palindrome (61788716).

The spelling of 61780000 in words is "sixty-one million, seven hundred eighty thousand".