145221481 has 2 divisors, whose sum is σ = 145221482. Its totient is φ = 145221480.

The previous prime is 145221469. The next prime is 145221547. The reversal of 145221481 is 184122541.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 144384256 + 837225 = 12016^2 + 915^2 .

It is an emirp because it is prime and its reverse (184122541) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 145221481 - 2⁹ = 145220969 is a prime.

It is a super-2 number, since 2×145221481² = 42178557087666722, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (145221421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 72610740 + 72610741.

It is an arithmetic number, because the mean of its divisors is an integer number (72610741).

Almost surely, 2^145221481 is an apocalyptic number.

It is an amenable number.

145221481 is a deficient number, since it is larger than the sum of its proper divisors (1).

145221481 is an equidigital number, since it uses as much as digits as its factorization.

145221481 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2560, while the sum is 28.

The square root of 145221481 is about 12050.7875676240. The cubic root of 145221481 is about 525.6261385054.

The spelling of 145221481 in words is "one hundred forty-five million, two hundred twenty-one thousand, four hundred eighty-one".