1387629281 has 8 divisors (see below), whose sum is σ = 1412558400. Its totient is φ = 1362770640.

The previous prime is 1387629263. The next prime is 1387629343. The reversal of 1387629281 is 1829267831.

It is a happy number.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1387629281 is a prime.

It is a super-2 number, since 2×1387629281² = 3851030042977153922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1387629211) 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, 22940 + ... + 57458.

It is an arithmetic number, because the mean of its divisors is an integer number (176569800).

Almost surely, 2^1387629281 is an apocalyptic number.

It is an amenable number.

1387629281 is a deficient number, since it is larger than the sum of its proper divisors (24929119).

1387629281 is an equidigital number, since it uses as much as digits as its factorization.

1387629281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35239.

The product of its digits is 290304, while the sum is 47.

The square root of 1387629281 is about 37250.8963784766. The cubic root of 1387629281 is about 1115.3841922444.

The spelling of 1387629281 in words is "one billion, three hundred eighty-seven million, six hundred twenty-nine thousand, two hundred eighty-one".