1621066423 has 4 divisors (see below), whose sum is σ = 1630122840. Its totient is φ = 1612010008.

The previous prime is 1621066409. The next prime is 1621066429. The reversal of 1621066423 is 3246601261.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1621066423 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 (1621066429) 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, 4527940 + ... + 4528297.

It is an arithmetic number, because the mean of its divisors is an integer number (407530710).

Almost surely, 2^1621066423 is an apocalyptic number.

1621066423 is a deficient number, since it is larger than the sum of its proper divisors (9056417).

1621066423 is an equidigital number, since it uses as much as digits as its factorization.

1621066423 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9056416.

The product of its (nonzero) digits is 10368, while the sum is 31.

The square root of 1621066423 is about 40262.4691617392. The cubic root of 1621066423 is about 1174.7179460010.

Adding to 1621066423 its reverse (3246601261), we get a palindrome (4867667684).

The spelling of 1621066423 in words is "one billion, six hundred twenty-one million, sixty-six thousand, four hundred twenty-three".