1281961995 has 16 divisors (see below), whose sum is σ = 2052552480. Its totient is φ = 683241984.

The previous prime is 1281961969. The next prime is 1281961997. The reversal of 1281961995 is 5991691821.

It is not a de Polignac number, because 1281961995 - 2¹⁵ = 1281929227 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1281961997) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6364 + ... + 51033.

It is an arithmetic number, because the mean of its divisors is an integer number (128284530).

Almost surely, 2^1281961995 is an apocalyptic number.

1281961995 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1281961995 is a deficient number, since it is larger than the sum of its proper divisors (770590485).

1281961995 is a wasteful number, since it uses less digits than its factorization.

1281961995 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58894.

The product of its digits is 349920, while the sum is 51.

The square root of 1281961995 is about 35804.4968544455. The cubic root of 1281961995 is about 1086.3215211199.

The spelling of 1281961995 in words is "one billion, two hundred eighty-one million, nine hundred sixty-one thousand, nine hundred ninety-five".