1621364643 has 12 divisors (see below), whose sum is σ = 2344472208. Its totient is φ = 1079755440.

The previous prime is 1621364623. The next prime is 1621364669. The reversal of 1621364643 is 3464631261.

1621364643 is a `hidden beast` number, since 1 + 6 + 2 + 1 + 3 + 6 + 4 + 643 = 666.

It is a de Polignac number, because none of the positive numbers 2^k-1621364643 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1621364598 and 1621364607.

It is not an unprimeable number, because it can be changed into a prime (1621364623) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 87255 + ... + 104192.

It is an arithmetic number, because the mean of its divisors is an integer number (195372684).

Almost surely, 2^1621364643 is an apocalyptic number.

1621364643 is a deficient number, since it is larger than the sum of its proper divisors (723107565).

1621364643 is a wasteful number, since it uses less digits than its factorization.

1621364643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 192394 (or 192391 counting only the distinct ones).

The product of its digits is 62208, while the sum is 36.

The square root of 1621364643 is about 40266.1724403996. The cubic root of 1621364643 is about 1174.7899773709.

The spelling of 1621364643 in words is "one billion, six hundred twenty-one million, three hundred sixty-four thousand, six hundred forty-three".