145120521 has 32 divisors (see below), whose sum is σ = 241532928. Its totient is φ = 75458880.

The previous prime is 145120489. The next prime is 145120523. The reversal of 145120521 is 125021541.

It is not a de Polignac number, because 145120521 - 2⁵ = 145120489 is a prime.

It is a super-2 number, since 2×145120521² = 42119931230622882, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (145120523) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 15640 + ... + 23126.

It is an arithmetic number, because the mean of its divisors is an integer number (7547904).

Almost surely, 2^145120521 is an apocalyptic number.

It is an amenable number.

145120521 is a deficient number, since it is larger than the sum of its proper divisors (96412407).

145120521 is a wasteful number, since it uses less digits than its factorization.

145120521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7581.

The product of its (nonzero) digits is 400, while the sum is 21.

The square root of 145120521 is about 12046.5979014824. The cubic root of 145120521 is about 525.5043027251.

The spelling of 145120521 in words is "one hundred forty-five million, one hundred twenty thousand, five hundred twenty-one".