145642152221 has 4 divisors (see below), whose sum is σ = 145764234012. Its totient is φ = 145520070432.

The previous prime is 145642152217. The next prime is 145642152223. The reversal of 145642152221 is 122251246541.

145642152221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 124881664996 + 20760487225 = 353386^2 + 144085^2 .

It is a cyclic number.

It is not a de Polignac number, because 145642152221 - 2² = 145642152217 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (145642152223) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 61039106 + ... + 61041491.

It is an arithmetic number, because the mean of its divisors is an integer number (36441058503).

Almost surely, 2^145642152221 is an apocalyptic number.

It is an amenable number.

145642152221 is a deficient number, since it is larger than the sum of its proper divisors (122081791).

145642152221 is a wasteful number, since it uses less digits than its factorization.

145642152221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 122081790.

The product of its digits is 38400, while the sum is 35.

Adding to 145642152221 its reverse (122251246541), we get a palindrome (267893398762).

The spelling of 145642152221 in words is "one hundred forty-five billion, six hundred forty-two million, one hundred fifty-two thousand, two hundred twenty-one".