1561400823 has 8 divisors (see below), whose sum is σ = 2082096000. Its totient is φ = 1040819768.

The previous prime is 1561400801. The next prime is 1561400833. The reversal of 1561400823 is 3280041651.

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

It is a cyclic number.

It is not a de Polignac number, because 1561400823 - 2⁶ = 1561400759 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1561400833) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11368 + ... + 57026.

It is an arithmetic number, because the mean of its divisors is an integer number (260262000).

Almost surely, 2^1561400823 is an apocalyptic number.

1561400823 is a deficient number, since it is larger than the sum of its proper divisors (520695177).

1561400823 is a wasteful number, since it uses less digits than its factorization.

1561400823 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57061.

The product of its (nonzero) digits is 5760, while the sum is 30.

The square root of 1561400823 is about 39514.5646945528. The cubic root of 1561400823 is about 1160.1250417625.

The spelling of 1561400823 in words is "one billion, five hundred sixty-one million, four hundred thousand, eight hundred twenty-three".