1281689125 has 16 divisors (see below), whose sum is σ = 1609760880. Its totient is φ = 1018804800.

The previous prime is 1281689119. The next prime is 1281689131. The reversal of 1281689125 is 5219861821.

It is an interprime number because it is at equal distance from previous prime (1281689119) and next prime (1281689131).

It can be written as a sum of positive squares in 8 ways, for example, as 325766401 + 955922724 = 18049^2 + 30918^2 .

It is not a de Polignac number, because 1281689125 - 2⁷ = 1281688997 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13030 + ... + 52279.

It is an arithmetic number, because the mean of its divisors is an integer number (100610055).

Almost surely, 2^1281689125 is an apocalyptic number.

It is an amenable number.

1281689125 is a deficient number, since it is larger than the sum of its proper divisors (328071755).

1281689125 is an equidigital number, since it uses as much as digits as its factorization.

1281689125 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65481 (or 65471 counting only the distinct ones).

The product of its digits is 69120, while the sum is 43.

The square root of 1281689125 is about 35800.6860967775. The cubic root of 1281689125 is about 1086.2444398989.

The spelling of 1281689125 in words is "one billion, two hundred eighty-one million, six hundred eighty-nine thousand, one hundred twenty-five".