1681689261 has 12 divisors (see below), whose sum is σ = 2608334592. Its totient is φ = 960965208.

The previous prime is 1681689253. The next prime is 1681689263. The reversal of 1681689261 is 1629861861.

It is not a de Polignac number, because 1681689261 - 2³ = 1681689253 is a prime.

It is a super-3 number, since 3×1681689261³ (a number of 29 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a self number, because there is not a number n which added to its sum of digits gives 1681689261.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1681689263) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5719885 + ... + 5720178.

It is an arithmetic number, because the mean of its divisors is an integer number (217361216).

Almost surely, 2^1681689261 is an apocalyptic number.

It is an amenable number.

1681689261 is a deficient number, since it is larger than the sum of its proper divisors (926645331).

1681689261 is a wasteful number, since it uses less digits than its factorization.

1681689261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11440080 (or 11440073 counting only the distinct ones).

The product of its digits is 248832, while the sum is 48.

The square root of 1681689261 is about 41008.4047604878. The cubic root of 1681689261 is about 1189.1827029346.

The spelling of 1681689261 in words is "one billion, six hundred eighty-one million, six hundred eighty-nine thousand, two hundred sixty-one".