172757987 has 4 divisors (see below), whose sum is σ = 173400480. Its totient is φ = 172115496.

The previous prime is 172757951. The next prime is 172757999. The reversal of 172757987 is 789757271.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 789757271 = 31 ⋅25476041.

It is a cyclic number.

It is not a de Polignac number, because 172757987 - 2⁸ = 172757731 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (172757287) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 320843 + ... + 321380.

It is an arithmetic number, because the mean of its divisors is an integer number (43350120).

Almost surely, 2^172757987 is an apocalyptic number.

172757987 is a deficient number, since it is larger than the sum of its proper divisors (642493).

172757987 is an equidigital number, since it uses as much as digits as its factorization.

172757987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 642492.

The product of its digits is 1728720, while the sum is 53.

The square root of 172757987 is about 13143.7432643825. The cubic root of 172757987 is about 556.9455158488.

The spelling of 172757987 in words is "one hundred seventy-two million, seven hundred fifty-seven thousand, nine hundred eighty-seven".