155421100 has 36 divisors (see below), whose sum is σ = 338525208. Its totient is φ = 61936000.

The previous prime is 155421001. The next prime is 155421103. The reversal of 155421100 is 1124551.

It is not an unprimeable number, because it can be changed into a prime (155421103) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 25335 + ... + 30865.

It is an arithmetic number, because the mean of its divisors is an integer number (9403478).

Almost surely, 2^155421100 is an apocalyptic number.

155421100 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

155421100 is an abundant number, since it is smaller than the sum of its proper divisors (183104108).

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

155421100 is a wasteful number, since it uses less digits than its factorization.

155421100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5826 (or 5819 counting only the distinct ones).

The product of its (nonzero) digits is 200, while the sum is 19.

The square root of 155421100 is about 12466.7999101614. The cubic root of 155421100 is about 537.6545508335.

Adding to 155421100 its reverse (1124551), we get a palindrome (156545651).

The spelling of 155421100 in words is "one hundred fifty-five million, four hundred twenty-one thousand, one hundred".