65998080 has 216 divisors, whose sum is σ = 242496072. Its totient is φ = 16515072.

The previous prime is 65998073. The next prime is 65998081. The reversal of 65998080 is 8089956.

It can be written as a sum of positive squares in 4 ways, for example, as 7750656 + 58247424 = 2784^2 + 7632^2 .

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65998081) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 195672 + ... + 196008.

It is an arithmetic number, because the mean of its divisors is an integer number (1122667).

Almost surely, 2^65998080 is an apocalyptic number.

65998080 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 65998080, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (121248036).

65998080 is an abundant number, since it is smaller than the sum of its proper divisors (176497992).

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

65998080 is a wasteful number, since it uses less digits than its factorization.

65998080 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 381 (or 364 counting only the distinct ones).

The product of its (nonzero) digits is 155520, while the sum is 45.

The square root of 65998080 is about 8123.9202359452. The cubic root of 65998080 is about 404.1200832460.

The spelling of 65998080 in words is "sixty-five million, nine hundred ninety-eight thousand, eighty".