1669940505 has 12 divisors (see below), whose sum is σ = 2894563620. Its totient is φ = 890634912.

The previous prime is 1669940497. The next prime is 1669940509. The reversal of 1669940505 is 5050499661.

It is a happy number.

1669940505 is a `hidden beast` number, since 16 + 6 + 99 + 40 + 505 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 212838921 + 1457101584 = 14589^2 + 38172^2 .

It is not a de Polignac number, because 1669940505 - 2³ = 1669940497 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45), and also a Moran number because the ratio is a prime number: 37109789 = 1669940505 / (1 + 6 + 6 + 9 + 9 + 4 + 0 + 5 + 0 + 5).

It is not an unprimeable number, because it can be changed into a prime (1669940509) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 18554850 + ... + 18554939.

It is an arithmetic number, because the mean of its divisors is an integer number (241213635).

Almost surely, 2^1669940505 is an apocalyptic number.

1669940505 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1669940505 is a deficient number, since it is larger than the sum of its proper divisors (1224623115).

1669940505 is a wasteful number, since it uses less digits than its factorization.

1669940505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37109800 (or 37109797 counting only the distinct ones).

The product of its (nonzero) digits is 291600, while the sum is 45.

The square root of 1669940505 is about 40864.9055425312. The cubic root of 1669940505 is about 1186.4069066559.

The spelling of 1669940505 in words is "one billion, six hundred sixty-nine million, nine hundred forty thousand, five hundred five".