1623144540581 has 2 divisors, whose sum is σ = 1623144540582. Its totient is φ = 1623144540580.

The previous prime is 1623144540569. The next prime is 1623144540583. The reversal of 1623144540581 is 1850454413261.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1379931837025 + 243212703556 = 1174705^2 + 493166^2 .

It is a cyclic number.

It is not a de Polignac number, because 1623144540581 - 2²² = 1623140346277 is a prime.

It is a super-2 number, since 2×1623144540581² (a number of 25 digits) contains 22 as substring.

Together with 1623144540583, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1623144540583) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 811572270290 + 811572270291.

It is an arithmetic number, because the mean of its divisors is an integer number (811572270291).

Almost surely, 2^{1623144540581} is an apocalyptic number.

It is an amenable number.

1623144540581 is a deficient number, since it is larger than the sum of its proper divisors (1).

1623144540581 is an equidigital number, since it uses as much as digits as its factorization.

1623144540581 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 460800, while the sum is 44.

The spelling of 1623144540581 in words is "one trillion, six hundred twenty-three billion, one hundred forty-four million, five hundred forty thousand, five hundred eighty-one".