1990272281 has 2 divisors, whose sum is σ = 1990272282. Its totient is φ = 1990272280.

The previous prime is 1990272257. The next prime is 1990272301. The reversal of 1990272281 is 1822720991.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1862785600 + 127486681 = 43160^2 + 11291^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1990272281 is a prime.

It is a super-2 number, since 2×1990272281² = 7922367505033885922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1990272241) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 995136140 + 995136141.

It is an arithmetic number, because the mean of its divisors is an integer number (995136141).

Almost surely, 2^1990272281 is an apocalyptic number.

It is an amenable number.

1990272281 is a deficient number, since it is larger than the sum of its proper divisors (1).

1990272281 is an equidigital number, since it uses as much as digits as its factorization.

1990272281 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 36288, while the sum is 41.

The square root of 1990272281 is about 44612.4677752756. The cubic root of 1990272281 is about 1257.8750361370.

The spelling of 1990272281 in words is "one billion, nine hundred ninety million, two hundred seventy-two thousand, two hundred eighty-one".