1428236381 has 16 divisors (see below), whose sum is σ = 1679677440. Its totient is φ = 1197270720.

The previous prime is 1428236347. The next prime is 1428236389. The reversal of 1428236381 is 1836328241.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 1428236381 - 2¹⁰ = 1428235357 is a prime.

It is a super-3 number, since 3×1428236381³ (a number of 28 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1428236389) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 148196 + ... + 157538.

It is an arithmetic number, because the mean of its divisors is an integer number (104979840).

Almost surely, 2^1428236381 is an apocalyptic number.

1428236381 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1428236381 is a deficient number, since it is larger than the sum of its proper divisors (251441059).

1428236381 is a wasteful number, since it uses less digits than its factorization.

1428236381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10436.

The product of its digits is 55296, while the sum is 38.

The square root of 1428236381 is about 37792.0147782571. The cubic root of 1428236381 is about 1126.1598260153.

The spelling of 1428236381 in words is "one billion, four hundred twenty-eight million, two hundred thirty-six thousand, three hundred eighty-one".