145855421 has 2 divisors, whose sum is σ = 145855422. Its totient is φ = 145855420.

The previous prime is 145855399. The next prime is 145855433. The reversal of 145855421 is 124558541.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 81631225 + 64224196 = 9035^2 + 8014^2 .

It is a cyclic number.

It is not a de Polignac number, because 145855421 - 2²⁶ = 78746557 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (145855921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 72927710 + 72927711.

It is an arithmetic number, because the mean of its divisors is an integer number (72927711).

Almost surely, 2^145855421 is an apocalyptic number.

It is an amenable number.

145855421 is a deficient number, since it is larger than the sum of its proper divisors (1).

145855421 is an equidigital number, since it uses as much as digits as its factorization.

145855421 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 32000, while the sum is 35.

The square root of 145855421 is about 12077.0617701492. The cubic root of 145855421 is about 526.3898724909.

The spelling of 145855421 in words is "one hundred forty-five million, eight hundred fifty-five thousand, four hundred twenty-one".