1287005961 has 16 divisors (see below), whose sum is σ = 1819286784. Its totient is φ = 806494464.

The previous prime is 1287005959. The next prime is 1287005969. The reversal of 1287005961 is 1695007821.

It is not a de Polignac number, because 1287005961 - 2¹ = 1287005959 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1287005969) 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, 24816 + ... + 56478.

It is an arithmetic number, because the mean of its divisors is an integer number (113705424).

Almost surely, 2^1287005961 is an apocalyptic number.

It is an amenable number.

1287005961 is a deficient number, since it is larger than the sum of its proper divisors (532280823).

1287005961 is a wasteful number, since it uses less digits than its factorization.

1287005961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32480.

The product of its (nonzero) digits is 30240, while the sum is 39.

The square root of 1287005961 is about 35874.8653098517. The cubic root of 1287005961 is about 1087.7443917382.

The spelling of 1287005961 in words is "one billion, two hundred eighty-seven million, five thousand, nine hundred sixty-one".