1621624406 has 4 divisors (see below), whose sum is σ = 2432436612. Its totient is φ = 810812202.

The previous prime is 1621624397. The next prime is 1621624421. The reversal of 1621624406 is 6044261261.

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 405406100 + ... + 405406103.

It is an arithmetic number, because the mean of its divisors is an integer number (608109153).

Almost surely, 2^1621624406 is an apocalyptic number.

1621624406 is a deficient number, since it is larger than the sum of its proper divisors (810812206).

1621624406 is an equidigital number, since it uses as much as digits as its factorization.

1621624406 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 810812205.

The product of its (nonzero) digits is 13824, while the sum is 32.

The square root of 1621624406 is about 40269.3978847462. The cubic root of 1621624406 is about 1174.8527127288.

Adding to 1621624406 its reverse (6044261261), we get a palindrome (7665885667).

The spelling of 1621624406 in words is "one billion, six hundred twenty-one million, six hundred twenty-four thousand, four hundred six".