145769821 has 2 divisors, whose sum is σ = 145769822. Its totient is φ = 145769820.

The previous prime is 145769797. The next prime is 145769839. The reversal of 145769821 is 128967541.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 84382596 + 61387225 = 9186^2 + 7835^2 .

It is a cyclic number.

It is not a de Polignac number, because 145769821 - 2¹⁷ = 145638749 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (145769861) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 72884910 + 72884911.

It is an arithmetic number, because the mean of its divisors is an integer number (72884911).

Almost surely, 2^145769821 is an apocalyptic number.

It is an amenable number.

145769821 is a deficient number, since it is larger than the sum of its proper divisors (1).

145769821 is an equidigital number, since it uses as much as digits as its factorization.

145769821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 120960, while the sum is 43.

The square root of 145769821 is about 12073.5173416863. The cubic root of 145769821 is about 526.2868759974.

The spelling of 145769821 in words is "one hundred forty-five million, seven hundred sixty-nine thousand, eight hundred twenty-one".