665618490 has 48 divisors (see below), whose sum is σ = 1738859616. Its totient is φ = 176652000.

The previous prime is 665618483. The next prime is 665618491. The reversal of 665618490 is 94816566.

665618490 is a `hidden beast` number, since 6 + 6 + 561 + 84 + 9 + 0 = 666.

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

It is not an unprimeable number, because it can be changed into a prime (665618491) 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, 1465 + ... + 36515.

It is an arithmetic number, because the mean of its divisors is an integer number (36226242).

Almost surely, 2^665618490 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 665618490, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (869429808).

665618490 is an abundant number, since it is smaller than the sum of its proper divisors (1073241126).

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

665618490 is a wasteful number, since it uses less digits than its factorization.

665618490 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35275 (or 35272 counting only the distinct ones).

The product of its (nonzero) digits is 311040, while the sum is 45.

The square root of 665618490 is about 25799.5831361671. The cubic root of 665618490 is about 873.1223912516.

The spelling of 665618490 in words is "six hundred sixty-five million, six hundred eighteen thousand, four hundred ninety".