64531998 has 16 divisors (see below), whose sum is σ = 143404560. Its totient is φ = 21510648.

The previous prime is 64531993. The next prime is 64532003. The reversal of 64531998 is 89913546.

It is a happy number.

64531998 is a `hidden beast` number, since 6 + 453 + 199 + 8 = 666.

It is an interprime number because it is at equal distance from previous prime (64531993) and next prime (64532003).

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64531993) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 597465 + ... + 597572.

It is an arithmetic number, because the mean of its divisors is an integer number (8962785).

Almost surely, 2^64531998 is an apocalyptic number.

64531998 is an abundant number, since it is smaller than the sum of its proper divisors (78872562).

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

64531998 is a wasteful number, since it uses less digits than its factorization.

64531998 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1195048 (or 1195042 counting only the distinct ones).

The product of its digits is 233280, while the sum is 45.

The square root of 64531998 is about 8033.1810635638. The cubic root of 64531998 is about 401.1052722866.

The spelling of 64531998 in words is "sixty-four million, five hundred thirty-one thousand, nine hundred ninety-eight".