1621396005 has 8 divisors (see below), whose sum is σ = 2594233632. Its totient is φ = 864744528.

The previous prime is 1621395983. The next prime is 1621396013. The reversal of 1621396005 is 5006931261.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1621396005 - 2⁷ = 1621395877 is a prime.

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 in 7 ways as a sum of consecutive naturals, for example, 54046519 + ... + 54046548.

It is an arithmetic number, because the mean of its divisors is an integer number (324279204).

Almost surely, 2^1621396005 is an apocalyptic number.

1621396005 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1621396005 is a deficient number, since it is larger than the sum of its proper divisors (972837627).

1621396005 is a wasteful number, since it uses less digits than its factorization.

1621396005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 108093075.

The product of its (nonzero) digits is 9720, while the sum is 33.

The square root of 1621396005 is about 40266.5618721043. The cubic root of 1621396005 is about 1174.7975519627.

The spelling of 1621396005 in words is "one billion, six hundred twenty-one million, three hundred ninety-six thousand, five".