1662423421 has 4 divisors (see below), whose sum is σ = 1760213052. Its totient is φ = 1564633792.

The previous prime is 1662423407. The next prime is 1662423467. The reversal of 1662423421 is 1243242661.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1243242661 = 37 ⋅33601153.

It can be written as a sum of positive squares in 2 ways, for example, as 1032915321 + 629508100 = 32139^2 + 25090^2 .

It is a cyclic number.

It is not a de Polignac number, because 1662423421 - 2⁷ = 1662423293 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1662423401) 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, 48894790 + ... + 48894823.

It is an arithmetic number, because the mean of its divisors is an integer number (440053263).

Almost surely, 2^1662423421 is an apocalyptic number.

It is an amenable number.

1662423421 is a deficient number, since it is larger than the sum of its proper divisors (97789631).

1662423421 is an equidigital number, since it uses as much as digits as its factorization.

1662423421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 97789630.

The product of its digits is 13824, while the sum is 31.

The square root of 1662423421 is about 40772.8269929864. The cubic root of 1662423421 is about 1184.6240615823.

The spelling of 1662423421 in words is "one billion, six hundred sixty-two million, four hundred twenty-three thousand, four hundred twenty-one".