155272121 has 2 divisors, whose sum is σ = 155272122. Its totient is φ = 155272120.

The previous prime is 155272109. The next prime is 155272133. The reversal of 155272121 is 121272551.

It is a balanced prime because it is at equal distance from previous prime (155272109) and next prime (155272133).

It can be written as a sum of positive squares in only one way, i.e., 144961600 + 10310521 = 12040^2 + 3211^2 .

It is an emirp because it is prime and its reverse (121272551) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-155272121 is a prime.

It is not a weakly prime, because it can be changed into another prime (155272141) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 77636060 + 77636061.

It is an arithmetic number, because the mean of its divisors is an integer number (77636061).

Almost surely, 2^155272121 is an apocalyptic number.

It is an amenable number.

155272121 is a deficient number, since it is larger than the sum of its proper divisors (1).

155272121 is an equidigital number, since it uses as much as digits as its factorization.

155272121 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1400, while the sum is 26.

The square root of 155272121 is about 12460.8234479107. The cubic root of 155272121 is about 537.4827062040.

The spelling of 155272121 in words is "one hundred fifty-five million, two hundred seventy-two thousand, one hundred twenty-one".