155116891 has 4 divisors (see below), whose sum is σ = 164241432. Its totient is φ = 145992352.

The previous prime is 155116883. The next prime is 155116903. The reversal of 155116891 is 198611551.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 155116891 - 2³ = 155116883 is a prime.

It is a super-2 number, since 2×155116891² = 48122499747011762, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 155116891.

It is not an unprimeable number, because it can be changed into a prime (155116391) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4562245 + ... + 4562278.

It is an arithmetic number, because the mean of its divisors is an integer number (41060358).

Almost surely, 2^155116891 is an apocalyptic number.

155116891 is a deficient number, since it is larger than the sum of its proper divisors (9124541).

155116891 is an equidigital number, since it uses as much as digits as its factorization.

155116891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9124540.

The product of its digits is 10800, while the sum is 37.

The square root of 155116891 is about 12454.5931687872. The cubic root of 155116891 is about 537.3035341822.

It can be divided in two parts, 1551 and 16891, that multiplied together give a triangular number (26197941 = T₇₂₃₈).

The spelling of 155116891 in words is "one hundred fifty-five million, one hundred sixteen thousand, eight hundred ninety-one".