145717561 has 4 divisors (see below), whose sum is σ = 158964624. Its totient is φ = 132470500.

The previous prime is 145717553. The next prime is 145717597. The reversal of 145717561 is 165717541.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 145717561 - 2³ = 145717553 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 145717561.

It is not an unprimeable number, because it can be changed into a prime (145717261) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6623515 + ... + 6623536.

It is an arithmetic number, because the mean of its divisors is an integer number (39741156).

Almost surely, 2^145717561 is an apocalyptic number.

145717561 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

145717561 is a deficient number, since it is larger than the sum of its proper divisors (13247063).

145717561 is a wasteful number, since it uses less digits than its factorization.

145717561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13247062.

The product of its digits is 29400, while the sum is 37.

The square root of 145717561 is about 12071.3529067789. The cubic root of 145717561 is about 526.2239753700.

The spelling of 145717561 in words is "one hundred forty-five million, seven hundred seventeen thousand, five hundred sixty-one".