65780000 has 240 divisors, whose sum is σ = 198386496. Its totient is φ = 21120000.

The previous prime is 65779999. The next prime is 65780027. The reversal of 65780000 is 8756.

It is a Harshad number since it is a multiple of its sum of digits (26).

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 2859989 + ... + 2860011.

Almost surely, 2^65780000 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 65780000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (99193248).

65780000 is an abundant number, since it is smaller than the sum of its proper divisors (132606496).

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

65780000 is a wasteful number, since it uses less digits than its factorization.

65780000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77 (or 54 counting only the distinct ones).

The product of its (nonzero) digits is 1680, while the sum is 26.

The square root of 65780000 is about 8110.4870383966. The cubic root of 65780000 is about 403.6744755488.

Adding to 65780000 its reverse (8756), we get a palindrome (65788756).

The spelling of 65780000 in words is "sixty-five million, seven hundred eighty thousand".