145196921 has 4 divisors (see below), whose sum is σ = 145410192. Its totient is φ = 144983652.

The previous prime is 145196903. The next prime is 145196923. The reversal of 145196921 is 129691541.

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 145196921 - 2¹⁴ = 145180537 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (145196923) 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, 105611 + ... + 106976.

It is an arithmetic number, because the mean of its divisors is an integer number (36352548).

Almost surely, 2^145196921 is an apocalyptic number.

It is an amenable number.

145196921 is a deficient number, since it is larger than the sum of its proper divisors (213271).

145196921 is an equidigital number, since it uses as much as digits as its factorization.

145196921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 213270.

The product of its digits is 19440, while the sum is 38.

The square root of 145196921 is about 12049.7685040004. The cubic root of 145196921 is about 525.5965053646.

The spelling of 145196921 in words is "one hundred forty-five million, one hundred ninety-six thousand, nine hundred twenty-one".