145561649 has 2 divisors, whose sum is σ = 145561650. Its totient is φ = 145561648.

The previous prime is 145561627. The next prime is 145561651. The reversal of 145561649 is 946165541.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 88830625 + 56731024 = 9425^2 + 7532^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-145561649 is a prime.

It is a Sophie Germain prime.

Together with 145561651, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (145561609) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 72780824 + 72780825.

It is an arithmetic number, because the mean of its divisors is an integer number (72780825).

Almost surely, 2^145561649 is an apocalyptic number.

It is an amenable number.

145561649 is a deficient number, since it is larger than the sum of its proper divisors (1).

145561649 is an equidigital number, since it uses as much as digits as its factorization.

145561649 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 129600, while the sum is 41.

The square root of 145561649 is about 12064.8932444510. The cubic root of 145561649 is about 526.0362288125.

The spelling of 145561649 in words is "one hundred forty-five million, five hundred sixty-one thousand, six hundred forty-nine".