669499020 has 168 divisors, whose sum is σ = 2155011264. Its totient is φ = 174555648.

The previous prime is 669499013. The next prime is 669499027. The reversal of 669499020 is 20994966.

It is an interprime number because it is at equal distance from previous prime (669499013) and next prime (669499027).

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 (669499027) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 55 ways as a sum of consecutive naturals, for example, 684772 + ... + 685748.

It is an arithmetic number, because the mean of its divisors is an integer number (12827448).

Almost surely, 2^669499020 is an apocalyptic number.

669499020 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 669499020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1077505632).

669499020 is an abundant number, since it is smaller than the sum of its proper divisors (1485512244).

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

669499020 is a wasteful number, since it uses less digits than its factorization.

669499020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1051 (or 1034 counting only the distinct ones).

The product of its (nonzero) digits is 209952, while the sum is 45.

The square root of 669499020 is about 25874.6791284452. The cubic root of 669499020 is about 874.8158611157.

The spelling of 669499020 in words is "six hundred sixty-nine million, four hundred ninety-nine thousand, twenty".