1387257987 has 32 divisors (see below), whose sum is σ = 2004201792. Its totient is φ = 850264064.

The previous prime is 1387257979. The next prime is 1387258051. The reversal of 1387257987 is 7897527831.

It is a cyclic number.

It is not a de Polignac number, because 1387257987 - 2³ = 1387257979 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1387257187) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 693673 + ... + 695669.

It is an arithmetic number, because the mean of its divisors is an integer number (62631306).

Almost surely, 2^1387257987 is an apocalyptic number.

1387257987 is a gapful number since it is divisible by the number (17) formed by its first and last digit.

1387257987 is a deficient number, since it is larger than the sum of its proper divisors (616943805).

1387257987 is a wasteful number, since it uses less digits than its factorization.

1387257987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2327.

The product of its digits is 5927040, while the sum is 57.

The square root of 1387257987 is about 37245.9123529012. The cubic root of 1387257987 is about 1115.2847006374.

The spelling of 1387257987 in words is "one billion, three hundred eighty-seven million, two hundred fifty-seven thousand, nine hundred eighty-seven".