1990494900801 has 45 divisors (see below), whose sum is σ = 3268572836529. Its totient is φ = 1206275895000.

The previous prime is 1990494900791. The next prime is 1990494900803. The reversal of 1990494900801 is 1080094940991.

The square root of 1990494900801 is 1410849.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 1990494900801 - 2¹³ = 1990494892609 is a prime.

It is a super-2 number, since 2×1990494900801² (a number of 25 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1990494900803) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 139666926 + ... + 139681176.

Almost surely, 2^{1990494900801} is an apocalyptic number.

1990494900801 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1990494900801 is the 1410849-th square number.

1990494900801 is the 705425-th centered octagonal number.

It is an amenable number.

1990494900801 is a deficient number, since it is larger than the sum of its proper divisors (1278077935728).

1990494900801 is an frugal number, since it uses more digits than its factorization.

1990494900801 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28536 (or 14265 counting only the distinct ones).

The product of its (nonzero) digits is 839808, while the sum is 54.

The spelling of 1990494900801 in words is "one trillion, nine hundred ninety billion, four hundred ninety-four million, nine hundred thousand, eight hundred one".