1281538969 has 4 divisors (see below), whose sum is σ = 1284149520. Its totient is φ = 1278928420.

The previous prime is 1281538957. The next prime is 1281539003. The reversal of 1281538969 is 9698351821.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1281538969 - 2⁹ = 1281538457 is a prime.

It is a super-2 number, since 2×1281538969² = 3284684258131165922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1281538939) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1304539 + ... + 1305520.

It is an arithmetic number, because the mean of its divisors is an integer number (321037380).

Almost surely, 2^1281538969 is an apocalyptic number.

It is an amenable number.

1281538969 is a deficient number, since it is larger than the sum of its proper divisors (2610551).

1281538969 is an equidigital number, since it uses as much as digits as its factorization.

1281538969 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2610550.

The product of its digits is 933120, while the sum is 52.

The square root of 1281538969 is about 35798.5889247048. The cubic root of 1281538969 is about 1086.2020186682.

The spelling of 1281538969 in words is "one billion, two hundred eighty-one million, five hundred thirty-eight thousand, nine hundred sixty-nine".