1999639861674 has 128 divisors (see below), whose sum is σ = 5190095554560. Its totient is φ = 498768171264.

The previous prime is 1999639861651. The next prime is 1999639861697. The reversal of 1999639861674 is 4761689369991.

It is an interprime number because it is at equal distance from previous prime (1999639861651) and next prime (1999639861697).

It is a super-2 number, since 2×1999639861674² (a number of 25 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (78).

It is a self number, because there is not a number n which added to its sum of digits gives 1999639861674.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 5925352 + ... + 6253724.

It is an arithmetic number, because the mean of its divisors is an integer number (40547621520).

Almost surely, 2^{1999639861674} is an apocalyptic number.

1999639861674 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 1999639861674, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2595047777280).

1999639861674 is an abundant number, since it is smaller than the sum of its proper divisors (3190455692886).

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

1999639861674 is a wasteful number, since it uses less digits than its factorization.

1999639861674 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 329004.

The product of its digits is 952342272, while the sum is 78.

The spelling of 1999639861674 in words is "one trillion, nine hundred ninety-nine billion, six hundred thirty-nine million, eight hundred sixty-one thousand, six hundred seventy-four".