155121099 has 8 divisors (see below), whose sum is σ = 236375040. Its totient is φ = 88640616.

The previous prime is 155121079. The next prime is 155121119. The reversal of 155121099 is 990121551.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (155121079) and next prime (155121119).

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 155121099 - 2¹² = 155117003 is a prime.

It is not an unprimeable number, because it can be changed into a prime (155121019) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3693339 + ... + 3693380.

It is an arithmetic number, because the mean of its divisors is an integer number (29546880).

Almost surely, 2^155121099 is an apocalyptic number.

155121099 is a deficient number, since it is larger than the sum of its proper divisors (81253941).

155121099 is an equidigital number, since it uses as much as digits as its factorization.

155121099 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7386729.

The product of its (nonzero) digits is 4050, while the sum is 33.

The square root of 155121099 is about 12454.7621013009. The cubic root of 155121099 is about 537.3083927823.

The spelling of 155121099 in words is "one hundred fifty-five million, one hundred twenty-one thousand, ninety-nine".