28717501 has 8 divisors (see below), whose sum is σ = 30933504. Its totient is φ = 26582160.

The previous prime is 28717499. The next prime is 28717553. The reversal of 28717501 is 10571782.

28717501 = T₄₃₇₄ + T₄₃₇₅ + T₄₃₇₆.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 28717501 - 2¹ = 28717499 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (31).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28717561) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19426 + ... + 20851.

It is an arithmetic number, because the mean of its divisors is an integer number (3866688).

Almost surely, 2^28717501 is an apocalyptic number.

28717501 is the 4376-th centered triangular number.

It is an amenable number.

28717501 is a deficient number, since it is larger than the sum of its proper divisors (2216003).

28717501 is a wasteful number, since it uses less digits than its factorization.

28717501 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40331.

The product of its (nonzero) digits is 3920, while the sum is 31.

The square root of 28717501 is about 5358.8712430884. The cubic root of 28717501 is about 306.2308089599.

The spelling of 28717501 in words is "twenty-eight million, seven hundred seventeen thousand, five hundred one".