2172987 has 20 divisors (see below), whose sum is σ = 3286360. Its totient is φ = 1430784.

The previous prime is 2172983. The next prime is 2172997. The reversal of 2172987 is 7892712.

It is not a de Polignac number, because 2172987 - 2² = 2172983 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2172983) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 11163 + ... + 11355.

It is an arithmetic number, because the mean of its divisors is an integer number (164318).

2^2172987 is an apocalyptic number.

2172987 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

2172987 is a deficient number, since it is larger than the sum of its proper divisors (1113373).

2172987 is a wasteful number, since it uses less digits than its factorization.

2172987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 344 (or 335 counting only the distinct ones).

The product of its digits is 14112, while the sum is 36.

The square root of 2172987 is about 1474.1054914761. The cubic root of 2172987 is about 129.5246346798.

The spelling of 2172987 in words is "two million, one hundred seventy-two thousand, nine hundred eighty-seven".