1990348301681 has 8 divisors (see below), whose sum is σ = 1994758443240. Its totient is φ = 1985942472192.

The previous prime is 1990348301597. The next prime is 1990348301723. The reversal of 1990348301681 is 1861038430991.

It can be written as a sum of positive squares in 4 ways, for example, as 279850522081 + 1710497779600 = 529009^2 + 1307860^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1990348301681 - 2²² = 1990344107377 is a prime.

It is a super-2 number, since 2×1990348301681² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1990348303681) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 152966 + ... + 2001023.

It is an arithmetic number, because the mean of its divisors is an integer number (249344805405).

Almost surely, 2^{1990348301681} is an apocalyptic number.

It is an amenable number.

1990348301681 is a deficient number, since it is larger than the sum of its proper divisors (4410141559).

1990348301681 is a wasteful number, since it uses less digits than its factorization.

1990348301681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2156035.

The product of its (nonzero) digits is 1119744, while the sum is 53.

The spelling of 1990348301681 in words is "one trillion, nine hundred ninety billion, three hundred forty-eight million, three hundred one thousand, six hundred eighty-one".