149221021 has 2 divisors, whose sum is σ = 149221022. Its totient is φ = 149221020.

The previous prime is 149220997. The next prime is 149221027. The reversal of 149221021 is 120122941.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 108388921 + 40832100 = 10411^2 + 6390^2 .

It is an emirp because it is prime and its reverse (120122941) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 149221021 - 2¹¹ = 149218973 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 149220983 and 149221001.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (149221027) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 74610510 + 74610511.

It is an arithmetic number, because the mean of its divisors is an integer number (74610511).

Almost surely, 2^149221021 is an apocalyptic number.

It is an amenable number.

149221021 is a deficient number, since it is larger than the sum of its proper divisors (1).

149221021 is an equidigital number, since it uses as much as digits as its factorization.

149221021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 288, while the sum is 22.

The square root of 149221021 is about 12215.6056337785. The cubic root of 149221021 is about 530.4079225760.

Adding to 149221021 its reverse (120122941), we get a palindrome (269343962).

The spelling of 149221021 in words is "one hundred forty-nine million, two hundred twenty-one thousand, twenty-one".