155021224 has 8 divisors (see below), whose sum is σ = 290664810. Its totient is φ = 77510608.

The previous prime is 155021221. The next prime is 155021227. The reversal of 155021224 is 422120551.

It is an interprime number because it is at equal distance from previous prime (155021221) and next prime (155021227).

It can be written as a sum of positive squares in only one way, i.e., 77757124 + 77264100 = 8818^2 + 8790^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a junction number, because it is equal to n+sod(n) for n = 155021195 and 155021204.

It is not an unprimeable number, because it can be changed into a prime (155021221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9688819 + ... + 9688834.

Almost surely, 2^155021224 is an apocalyptic number.

It is an amenable number.

155021224 is a deficient number, since it is larger than the sum of its proper divisors (135643586).

155021224 is a wasteful number, since it uses less digits than its factorization.

155021224 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19377659 (or 19377655 counting only the distinct ones).

The product of its (nonzero) digits is 800, while the sum is 22.

The square root of 155021224 is about 12450.7519451638. The cubic root of 155021224 is about 537.1930523647.

Adding to 155021224 its reverse (422120551), we get a palindrome (577141775).

The spelling of 155021224 in words is "one hundred fifty-five million, twenty-one thousand, two hundred twenty-four".