19906670281 has 9 divisors (see below), whose sum is σ = 20035465191. Its totient is φ = 19778700744.

The previous prime is 19906670261. The next prime is 19906670297. The reversal of 19906670281 is 18207660991.

The square root of 19906670281 is 141091.

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

It can be written as a sum of positive squares in only one way, i.e., 2656474681 + 17250195600 = 51541^2 + 131340^2 .

It is not a de Polignac number, because 19906670281 - 2⁷ = 19906670153 is a prime.

It is a super-2 number, since 2×19906670281² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19906670221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 28076755 + ... + 28077463.

It is an arithmetic number, because the mean of its divisors is an integer number (2226162799).

Almost surely, 2^19906670281 is an apocalyptic number.

19906670281 is the 141091-st square number.

19906670281 is the 70546-th centered octagonal number.

It is an amenable number.

19906670281 is a deficient number, since it is larger than the sum of its proper divisors (128794910).

19906670281 is an frugal number, since it uses more digits than its factorization.

19906670281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1816 (or 908 counting only the distinct ones).

The product of its (nonzero) digits is 326592, while the sum is 49.

Multiplying 19906670281 by its sum of digits (49), we get a square (975426843769 = 987637²).

The spelling of 19906670281 in words is "nineteen billion, nine hundred six million, six hundred seventy thousand, two hundred eighty-one".