161226521 has 8 divisors (see below), whose sum is σ = 170823240. Its totient is φ = 151642368.

The previous prime is 161226511. The next prime is 161226539. The reversal of 161226521 is 125622161.

161226521 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 22458121 + 138768400 = 4739^2 + 11780^2 .

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-161226521 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161226511) 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, 41615 + ... + 45323.

It is an arithmetic number, because the mean of its divisors is an integer number (21352905).

Almost surely, 2^161226521 is an apocalyptic number.

It is an amenable number.

161226521 is a deficient number, since it is larger than the sum of its proper divisors (9596719).

161226521 is a wasteful number, since it uses less digits than its factorization.

161226521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6283.

The product of its digits is 1440, while the sum is 26.

The square root of 161226521 is about 12697.5005808230. The cubic root of 161226521 is about 544.2671979355.

Adding to 161226521 its reverse (125622161), we get a palindrome (286848682).

The spelling of 161226521 in words is "one hundred sixty-one million, two hundred twenty-six thousand, five hundred twenty-one".