1387520291 has 2 divisors, whose sum is σ = 1387520292. Its totient is φ = 1387520290.

The previous prime is 1387520249. The next prime is 1387520317. The reversal of 1387520291 is 1920257831.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1387520291 - 2²² = 1383325987 is a prime.

It is not a weakly prime, because it can be changed into another prime (1387520221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 693760145 + 693760146.

It is an arithmetic number, because the mean of its divisors is an integer number (693760146).

Almost surely, 2^1387520291 is an apocalyptic number.

1387520291 is a deficient number, since it is larger than the sum of its proper divisors (1).

1387520291 is an equidigital number, since it uses as much as digits as its factorization.

1387520291 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 30240, while the sum is 38.

The square root of 1387520291 is about 37249.4334319329. The cubic root of 1387520291 is about 1115.3549892222.

The spelling of 1387520291 in words is "one billion, three hundred eighty-seven million, five hundred twenty thousand, two hundred ninety-one".