65515998 has 24 divisors (see below), whose sum is σ = 132266952. Its totient is φ = 21634704.

The previous prime is 65515997. The next prime is 65516023. The reversal of 65515998 is 89951556.

It is a happy number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65515997) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 96436 + ... + 97112.

It is an arithmetic number, because the mean of its divisors is an integer number (5511123).

Almost surely, 2^65515998 is an apocalyptic number.

65515998 is an abundant number, since it is smaller than the sum of its proper divisors (66750954).

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

65515998 is a wasteful number, since it uses less digits than its factorization.

65515998 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 936 (or 809 counting only the distinct ones).

The product of its digits is 486000, while the sum is 48.

The square root of 65515998 is about 8094.1953275171. The cubic root of 65515998 is about 403.1337146364.

It can be divided in two parts, 655 and 15998, that added together give a triangular number (16653 = T₁₈₂).

The spelling of 65515998 in words is "sixty-five million, five hundred fifteen thousand, nine hundred ninety-eight".