1427451981 has 4 divisors (see below), whose sum is σ = 1903269312. Its totient is φ = 951634652.

The previous prime is 1427451979. The next prime is 1427451983. The reversal of 1427451981 is 1891547241.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1891547241 = 3 ⋅630515747.

It is an interprime number because it is at equal distance from previous prime (1427451979) and next prime (1427451983).

It is a cyclic number.

It is not a de Polignac number, because 1427451981 - 2¹ = 1427451979 is a prime.

It is a super-2 number, since 2×1427451981² = 4075238316121648722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1427451983) 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 3 ways as a sum of consecutive naturals, for example, 237908661 + ... + 237908666.

It is an arithmetic number, because the mean of its divisors is an integer number (475817328).

Almost surely, 2^1427451981 is an apocalyptic number.

It is an amenable number.

1427451981 is a deficient number, since it is larger than the sum of its proper divisors (475817331).

1427451981 is an equidigital number, since it uses as much as digits as its factorization.

1427451981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 475817330.

The product of its digits is 80640, while the sum is 42.

The square root of 1427451981 is about 37781.6354992740. The cubic root of 1427451981 is about 1125.9536226294.

The spelling of 1427451981 in words is "one billion, four hundred twenty-seven million, four hundred fifty-one thousand, nine hundred eighty-one".