1691518381412 has 24 divisors (see below), whose sum is σ = 3030121226496. Its totient is φ = 825852578688.

The previous prime is 1691518381349. The next prime is 1691518381477. The reversal of 1691518381412 is 2141838151961.

It is a super-2 number, since 2×1691518381412² (a number of 25 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10308248 + ... + 10471055.

It is an arithmetic number, because the mean of its divisors is an integer number (126255051104).

Almost surely, 2^{1691518381412} is an apocalyptic number.

It is an amenable number.

1691518381412 is a deficient number, since it is larger than the sum of its proper divisors (1338602845084).

1691518381412 is a wasteful number, since it uses less digits than its factorization.

1691518381412 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20779787 (or 20779785 counting only the distinct ones).

The product of its digits is 414720, while the sum is 50.

The spelling of 1691518381412 in words is "one trillion, six hundred ninety-one billion, five hundred eighteen million, three hundred eighty-one thousand, four hundred twelve".