155463221 has 2 divisors, whose sum is σ = 155463222. Its totient is φ = 155463220.

The previous prime is 155463211. The next prime is 155463227. The reversal of 155463221 is 122364551.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 131560900 + 23902321 = 11470^2 + 4889^2 .

It is an emirp because it is prime and its reverse (122364551) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 155463221 - 2⁶ = 155463157 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (155463227) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 77731610 + 77731611.

It is an arithmetic number, because the mean of its divisors is an integer number (77731611).

Almost surely, 2^155463221 is an apocalyptic number.

It is an amenable number.

155463221 is a deficient number, since it is larger than the sum of its proper divisors (1).

155463221 is an equidigital number, since it uses as much as digits as its factorization.

155463221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7200, while the sum is 29.

The square root of 155463221 is about 12468.4891225842. The cubic root of 155463221 is about 537.7031167442.

The spelling of 155463221 in words is "one hundred fifty-five million, four hundred sixty-three thousand, two hundred twenty-one".