1393919621 has 2 divisors, whose sum is σ = 1393919622. Its totient is φ = 1393919620.

The previous prime is 1393919587. The next prime is 1393919627. The reversal of 1393919621 is 1269193931.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1273776100 + 120143521 = 35690^2 + 10961^2 .

It is a cyclic number.

It is not a de Polignac number, because 1393919621 - 2¹⁰ = 1393918597 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1393919627) 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 as a sum of consecutive naturals, namely, 696959810 + 696959811.

It is an arithmetic number, because the mean of its divisors is an integer number (696959811).

Almost surely, 2^1393919621 is an apocalyptic number.

It is an amenable number.

1393919621 is a deficient number, since it is larger than the sum of its proper divisors (1).

1393919621 is an equidigital number, since it uses as much as digits as its factorization.

1393919621 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 78732, while the sum is 44.

The square root of 1393919621 is about 37335.2329710155. The cubic root of 1393919621 is about 1117.0670554206.

The spelling of 1393919621 in words is "one billion, three hundred ninety-three million, nine hundred nineteen thousand, six hundred twenty-one".