155628779 has 4 divisors (see below), whose sum is σ = 157169760. Its totient is φ = 154087800.

The previous prime is 155628769. The next prime is 155628793. The reversal of 155628779 is 977826551.

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 155628779 - 2⁴ = 155628763 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (155628719) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 770339 + ... + 770540.

It is an arithmetic number, because the mean of its divisors is an integer number (39292440).

Almost surely, 2^155628779 is an apocalyptic number.

155628779 is a deficient number, since it is larger than the sum of its proper divisors (1540981).

155628779 is a wasteful number, since it uses less digits than its factorization.

155628779 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1540980.

The product of its digits is 1058400, while the sum is 50.

The square root of 155628779 is about 12475.1264121852. The cubic root of 155628779 is about 537.8939217252.

The spelling of 155628779 in words is "one hundred fifty-five million, six hundred twenty-eight thousand, seven hundred seventy-nine".