1281669481 has 6 divisors (see below), whose sum is σ = 1312170810. Its totient is φ = 1251861408.

The previous prime is 1281669469. The next prime is 1281669517. The reversal of 1281669481 is 1849661821.

It can be written as a sum of positive squares in only one way, i.e., 1258475625 + 23193856 = 35475^2 + 4816^2 .

It is not a de Polignac number, because 1281669481 - 2¹⁹ = 1281145193 is a prime.

It is a super-2 number, since 2×1281669481² = 3285353317053618722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1281669421) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 344736 + ... + 348433.

It is an arithmetic number, because the mean of its divisors is an integer number (218695135).

Almost surely, 2^1281669481 is an apocalyptic number.

It is an amenable number.

1281669481 is a deficient number, since it is larger than the sum of its proper divisors (30501329).

1281669481 is an frugal number, since it uses more digits than its factorization.

1281669481 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 693255 (or 693212 counting only the distinct ones).

The product of its digits is 165888, while the sum is 46.

The square root of 1281669481 is about 35800.4117434423. The cubic root of 1281669481 is about 1086.2388903746.

The spelling of 1281669481 in words is "one billion, two hundred eighty-one million, six hundred sixty-nine thousand, four hundred eighty-one".