1428571381 has 4 divisors (see below), whose sum is σ = 1455525612. Its totient is φ = 1401617152.

The previous prime is 1428571379. The next prime is 1428571409. The reversal of 1428571381 is 1831758241.

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

It can be written as a sum of positive squares in 2 ways, for example, as 879419025 + 549152356 = 29655^2 + 23434^2 .

It is a cyclic number.

It is not a de Polignac number, because 1428571381 - 2¹ = 1428571379 is a prime.

It is a super-2 number, since 2×1428571381² = 4081632381224494322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1428571181) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13477036 + ... + 13477141.

It is an arithmetic number, because the mean of its divisors is an integer number (363881403).

Almost surely, 2^1428571381 is an apocalyptic number.

It is an amenable number.

1428571381 is a deficient number, since it is larger than the sum of its proper divisors (26954231).

1428571381 is an equidigital number, since it uses as much as digits as its factorization.

1428571381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26954230.

The product of its digits is 53760, while the sum is 40.

The square root of 1428571381 is about 37796.4466716119. The cubic root of 1428571381 is about 1126.2478679423.

The spelling of 1428571381 in words is "one billion, four hundred twenty-eight million, five hundred seventy-one thousand, three hundred eighty-one".