155729987 has 12 divisors (see below), whose sum is σ = 189032976. Its totient is φ = 127678320.

The previous prime is 155729983. The next prime is 155729989. The reversal of 155729987 is 789927551.

It is a happy number.

It is not a de Polignac number, because 155729987 - 2² = 155729983 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (155729983) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 67964 + ... + 70217.

It is an arithmetic number, because the mean of its divisors is an integer number (15752748).

Almost surely, 2^155729987 is an apocalyptic number.

155729987 is a deficient number, since it is larger than the sum of its proper divisors (33302989).

155729987 is a wasteful number, since it uses less digits than its factorization.

155729987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 138218 (or 138211 counting only the distinct ones).

The product of its digits is 1587600, while the sum is 53.

The square root of 155729987 is about 12479.1821446760. The cubic root of 155729987 is about 538.0104969322.

The spelling of 155729987 in words is "one hundred fifty-five million, seven hundred twenty-nine thousand, nine hundred eighty-seven".