161621125763 has 4 divisors (see below), whose sum is σ = 161985959448. Its totient is φ = 161256292080.

The previous prime is 161621125753. The next prime is 161621125789. The reversal of 161621125763 is 367521126161.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 367521126161 = 7 ⋅52503018023.

It is a cyclic number.

It is not a de Polignac number, because 161621125763 - 2¹² = 161621121667 is a prime.

It is a super-2 number, since 2×161621125763² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 161621125763.

It is not an unprimeable number, because it can be changed into a prime (161621125723) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 182416178 + ... + 182417063.

It is an arithmetic number, because the mean of its divisors is an integer number (40496489862).

Almost surely, 2^161621125763 is an apocalyptic number.

161621125763 is a deficient number, since it is larger than the sum of its proper divisors (364833685).

161621125763 is an equidigital number, since it uses as much as digits as its factorization.

161621125763 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 364833684.

The product of its digits is 90720, while the sum is 41.

The spelling of 161621125763 in words is "one hundred sixty-one billion, six hundred twenty-one million, one hundred twenty-five thousand, seven hundred sixty-three".