669369918 has 64 divisors (see below), whose sum is σ = 1583972352. Its totient is φ = 184537440.

The previous prime is 669369907. The next prime is 669369919. The reversal of 669369918 is 819963966.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (669369919) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 680455 + ... + 681437.

It is an arithmetic number, because the mean of its divisors is an integer number (24749568).

Almost surely, 2^669369918 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 669369918, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (791986176).

669369918 is an abundant number, since it is smaller than the sum of its proper divisors (914602434).

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

669369918 is a wasteful number, since it uses less digits than its factorization.

669369918 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1549.

The product of its digits is 3779136, while the sum is 57.

The square root of 669369918 is about 25872.1842525907. The cubic root of 669369918 is about 874.7596261627.

The spelling of 669369918 in words is "six hundred sixty-nine million, three hundred sixty-nine thousand, nine hundred eighteen".