155521002 has 64 divisors (see below), whose sum is σ = 390700800. Its totient is φ = 41009472.

The previous prime is 155520983. The next prime is 155521007. The reversal of 155521002 is 200125551.

155521002 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a self number, because there is not a number n which added to its sum of digits gives 155521002.

It is not an unprimeable number, because it can be changed into a prime (155521007) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 23848 + ... + 29660.

It is an arithmetic number, because the mean of its divisors is an integer number (6104700).

Almost surely, 2^155521002 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 155521002, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (195350400).

155521002 is an abundant number, since it is smaller than the sum of its proper divisors (235179798).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

155521002 is a wasteful number, since it uses less digits than its factorization.

155521002 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5852 (or 5838 counting only the distinct ones).

The product of its (nonzero) digits is 500, while the sum is 21.

The square root of 155521002 is about 12470.8059883874. The cubic root of 155521002 is about 537.7697245143.

Adding to 155521002 its reverse (200125551), we get a palindrome (355646553).

The spelling of 155521002 in words is "one hundred fifty-five million, five hundred twenty-one thousand, two".