155969979 has 16 divisors (see below), whose sum is σ = 228528000. Its totient is φ = 93834560.

The previous prime is 155969977. The next prime is 155970047. The reversal of 155969979 is 979969551.

It is a cyclic number.

It is not a de Polignac number, because 155969979 - 2¹ = 155969977 is a prime.

It is not an unprimeable number, because it can be changed into a prime (155969971) 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 15 ways as a sum of consecutive naturals, for example, 12729 + ... + 21770.

It is an arithmetic number, because the mean of its divisors is an integer number (14283000).

Almost surely, 2^155969979 is an apocalyptic number.

155969979 is a deficient number, since it is larger than the sum of its proper divisors (72558021).

155969979 is a wasteful number, since it uses less digits than its factorization.

155969979 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34650.

The product of its digits is 6889050, while the sum is 60.

The square root of 155969979 is about 12488.7941371455. The cubic root of 155969979 is about 538.2867270648.

The spelling of 155969979 in words is "one hundred fifty-five million, nine hundred sixty-nine thousand, nine hundred seventy-nine".