1561416521 has 8 divisors (see below), whose sum is σ = 1846009920. Its totient is φ = 1292206608.

The previous prime is 1561416511. The next prime is 1561416529. The reversal of 1561416521 is 1256141651.

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

It is not a de Polignac number, because 1561416521 - 2⁶ = 1561416457 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1561416529) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3845651 + ... + 3846056.

It is an arithmetic number, because the mean of its divisors is an integer number (230751240).

Almost surely, 2^1561416521 is an apocalyptic number.

It is an amenable number.

1561416521 is a deficient number, since it is larger than the sum of its proper divisors (284593399).

1561416521 is an equidigital number, since it uses as much as digits as its factorization.

1561416521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7691743.

The product of its digits is 7200, while the sum is 32.

The square root of 1561416521 is about 39514.7633296721. The cubic root of 1561416521 is about 1160.1289296349.

The spelling of 1561416521 in words is "one billion, five hundred sixty-one million, four hundred sixteen thousand, five hundred twenty-one".