1689606405 has 16 divisors (see below), whose sum is σ = 3003744960. Its totient is φ = 901123344.

The previous prime is 1689606377. The next prime is 1689606409. The reversal of 1689606405 is 5046069861.

It is not a de Polignac number, because 1689606405 - 2⁷ = 1689606277 is a prime.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1689606409) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6257667 + ... + 6257936.

It is an arithmetic number, because the mean of its divisors is an integer number (187734060).

Almost surely, 2^1689606405 is an apocalyptic number.

1689606405 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1689606405 is a deficient number, since it is larger than the sum of its proper divisors (1314138555).

1689606405 is a wasteful number, since it uses less digits than its factorization.

1689606405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12515617 (or 12515611 counting only the distinct ones).

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

The square root of 1689606405 is about 41104.8221623692. The cubic root of 1689606405 is about 1191.0459473800.

The spelling of 1689606405 in words is "one billion, six hundred eighty-nine million, six hundred six thousand, four hundred five".