1667422381 has 4 divisors (see below), whose sum is σ = 1675886652. Its totient is φ = 1658958112.

The previous prime is 1667422369. The next prime is 1667422429. The reversal of 1667422381 is 1832247661.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1832247661 = 499 ⋅3671839.

It can be written as a sum of positive squares in 2 ways, for example, as 1513910281 + 153512100 = 38909^2 + 12390^2 .

It is a cyclic number.

It is not a de Polignac number, because 1667422381 - 2¹⁵ = 1667389613 is a prime.

It is a super-2 number, since 2×1667422381² = 5560594793319418322, 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 (1667422321) 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, 4231840 + ... + 4232233.

It is an arithmetic number, because the mean of its divisors is an integer number (418971663).

Almost surely, 2^1667422381 is an apocalyptic number.

It is an amenable number.

1667422381 is a deficient number, since it is larger than the sum of its proper divisors (8464271).

1667422381 is an equidigital number, since it uses as much as digits as its factorization.

1667422381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8464270.

The product of its digits is 96768, while the sum is 40.

The square root of 1667422381 is about 40834.0835699786. The cubic root of 1667422381 is about 1185.8102741022.

The spelling of 1667422381 in words is "one billion, six hundred sixty-seven million, four hundred twenty-two thousand, three hundred eighty-one".