145317021 has 8 divisors (see below), whose sum is σ = 195567264. Its totient is φ = 95972400.

The previous prime is 145317017. The next prime is 145317023. The reversal of 145317021 is 120713541.

145317021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 145317021 - 2² = 145317017 is a prime.

It is a super-2 number, since 2×145317021² = 42234073184628882, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 145316982 and 145317000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (145317023) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 226030 + ... + 226671.

It is an arithmetic number, because the mean of its divisors is an integer number (24445908).

Almost surely, 2^145317021 is an apocalyptic number.

It is an amenable number.

145317021 is a deficient number, since it is larger than the sum of its proper divisors (50250243).

145317021 is a wasteful number, since it uses less digits than its factorization.

145317021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 452811.

The product of its (nonzero) digits is 840, while the sum is 24.

The square root of 145317021 is about 12054.7509721271. The cubic root of 145317021 is about 525.7413815861.

The spelling of 145317021 in words is "one hundred forty-five million, three hundred seventeen thousand, twenty-one".