145611989 has 2 divisors, whose sum is σ = 145611990. Its totient is φ = 145611988.

The previous prime is 145611979. The next prime is 145611997. The reversal of 145611989 is 989116541.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 131285764 + 14326225 = 11458^2 + 3785^2 .

It is a cyclic number.

It is not a de Polignac number, because 145611989 - 2²⁰ = 144563413 is a prime.

It is a super-2 number, since 2×145611989² = 42405702681072242, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (145611979) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 72805994 + 72805995.

It is an arithmetic number, because the mean of its divisors is an integer number (72805995).

Almost surely, 2^145611989 is an apocalyptic number.

It is an amenable number.

145611989 is a deficient number, since it is larger than the sum of its proper divisors (1).

145611989 is an equidigital number, since it uses as much as digits as its factorization.

145611989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 77760, while the sum is 44.

The square root of 145611989 is about 12066.9792823225. The cubic root of 145611989 is about 526.0968620262.

The spelling of 145611989 in words is "one hundred forty-five million, six hundred eleven thousand, nine hundred eighty-nine".