1287990153998 has 4 divisors (see below), whose sum is σ = 1931985231000. Its totient is φ = 643995076998.

The previous prime is 1287990153991. The next prime is 1287990154027. The reversal of 1287990153998 is 8993510997821.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1287990153991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321997538498 + ... + 321997538501.

It is an arithmetic number, because the mean of its divisors is an integer number (482996307750).

Almost surely, 2^{1287990153998} is an apocalyptic number.

1287990153998 is a deficient number, since it is larger than the sum of its proper divisors (643995077002).

1287990153998 is an equidigital number, since it uses as much as digits as its factorization.

1287990153998 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 643995077001.

The product of its (nonzero) digits is 88179840, while the sum is 71.

The spelling of 1287990153998 in words is "one trillion, two hundred eighty-seven billion, nine hundred ninety million, one hundred fifty-three thousand, nine hundred ninety-eight".