155381997 has 8 divisors (see below), whose sum is σ = 216183744. Its totient is φ = 99084128.

The previous prime is 155381983. The next prime is 155382001. The reversal of 155381997 is 799183551.

155381997 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is not a de Polignac number, because 155381997 - 2¹⁶ = 155316461 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (155381927) 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, 1125888 + ... + 1126025.

It is an arithmetic number, because the mean of its divisors is an integer number (27022968).

Almost surely, 2^155381997 is an apocalyptic number.

It is an amenable number.

155381997 is a deficient number, since it is larger than the sum of its proper divisors (60801747).

155381997 is a wasteful number, since it uses less digits than its factorization.

155381997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2251939.

The product of its digits is 340200, while the sum is 48.

The square root of 155381997 is about 12465.2315261290. The cubic root of 155381997 is about 537.6094568505.

The spelling of 155381997 in words is "one hundred fifty-five million, three hundred eighty-one thousand, nine hundred ninety-seven".