155320400 has 30 divisors (see below), whose sum is σ = 373158222. Its totient is φ = 62128000.

The previous prime is 155320379. The next prime is 155320409. The reversal of 155320400 is 4023551.

It can be written as a sum of positive squares in 3 ways, for example, as 2155024 + 153165376 = 1468^2 + 12376^2 .

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (155320409) 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, 193751 + ... + 194550.

Almost surely, 2^155320400 is an apocalyptic number.

155320400 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

155320400 is an abundant number, since it is smaller than the sum of its proper divisors (217837822).

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

155320400 is a wasteful number, since it uses less digits than its factorization.

155320400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 388319 (or 388308 counting only the distinct ones).

The product of its (nonzero) digits is 600, while the sum is 20.

The square root of 155320400 is about 12462.7605288716. The cubic root of 155320400 is about 537.5384072069.

Adding to 155320400 its reverse (4023551), we get a palindrome (159343951).

The spelling of 155320400 in words is "one hundred fifty-five million, three hundred twenty thousand, four hundred".