155021481 has 6 divisors (see below), whose sum is σ = 223919930. Its totient is φ = 103347648.

The previous prime is 155021479. The next prime is 155021509. The reversal of 155021481 is 184120551.

155021481 is a `hidden beast` number, since 15 + 502 + 148 + 1 = 666.

155021481 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 147403881 + 7617600 = 12141^2 + 2760^2 .

It is not a de Polignac number, because 155021481 - 2¹ = 155021479 is a prime.

It is a super-2 number, since 2×155021481² = 48063319142866722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (155021401) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 8612296 + ... + 8612313.

Almost surely, 2^155021481 is an apocalyptic number.

It is an amenable number.

155021481 is a deficient number, since it is larger than the sum of its proper divisors (68898449).

155021481 is a wasteful number, since it uses less digits than its factorization.

155021481 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17224615 (or 17224612 counting only the distinct ones).

The product of its (nonzero) digits is 1600, while the sum is 27.

The square root of 155021481 is about 12450.7622658213. The cubic root of 155021481 is about 537.1933492242.

The spelling of 155021481 in words is "one hundred fifty-five million, twenty-one thousand, four hundred eighty-one".