1621563622687 has 2 divisors, whose sum is σ = 1621563622688. Its totient is φ = 1621563622686.

The previous prime is 1621563622607. The next prime is 1621563622727. The reversal of 1621563622687 is 7862263651261.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1621563622687 - 2¹⁹ = 1621563098399 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1621563622607) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 810781811343 + 810781811344.

It is an arithmetic number, because the mean of its divisors is an integer number (810781811344).

Almost surely, 2^{1621563622687} is an apocalyptic number.

1621563622687 is a deficient number, since it is larger than the sum of its proper divisors (1).

1621563622687 is an equidigital number, since it uses as much as digits as its factorization.

1621563622687 is an evil number, because the sum of its binary digits is even.

The product of its digits is 8709120, while the sum is 55.

The spelling of 1621563622687 in words is "one trillion, six hundred twenty-one billion, five hundred sixty-three million, six hundred twenty-two thousand, six hundred eighty-seven".