1287121431 has 8 divisors (see below), whose sum is σ = 1716729840. Its totient is φ = 857796992.

The previous prime is 1287121399. The next prime is 1287121447. The reversal of 1287121431 is 1341217821.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1287121431 - 2⁵ = 1287121399 is a prime.

It is a super-2 number, since 2×1287121431² = 3313363156278975522, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1287121831) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 60180 + ... + 78713.

It is an arithmetic number, because the mean of its divisors is an integer number (214591230).

Almost surely, 2^1287121431 is an apocalyptic number.

1287121431 is a deficient number, since it is larger than the sum of its proper divisors (429608409).

1287121431 is a wasteful number, since it uses less digits than its factorization.

1287121431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 141985.

The product of its digits is 2688, while the sum is 30.

The square root of 1287121431 is about 35876.4746177770. The cubic root of 1287121431 is about 1087.7769215251.

The spelling of 1287121431 in words is "one billion, two hundred eighty-seven million, one hundred twenty-one thousand, four hundred thirty-one".