155222400 has 384 divisors, whose sum is σ = 576748800. Its totient is φ = 36495360.

The previous prime is 155222357. The next prime is 155222447. The reversal of 155222400 is 4222551.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (384).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 4195182 + ... + 4195218.

It is an arithmetic number, because the mean of its divisors is an integer number (1501950).

Almost surely, 2^155222400 is an apocalyptic number.

155222400 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 155222400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (288374400).

155222400 is an abundant number, since it is smaller than the sum of its proper divisors (421526400).

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

155222400 is a wasteful number, since it uses less digits than its factorization.

155222400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 106 (or 89 counting only the distinct ones).

The product of its (nonzero) digits is 800, while the sum is 21.

The square root of 155222400 is about 12458.8281952999. The cubic root of 155222400 is about 537.4253294504.

Adding to 155222400 its reverse (4222551), we get a palindrome (159444951).

The spelling of 155222400 in words is "one hundred fifty-five million, two hundred twenty-two thousand, four hundred".