28745661 has 8 divisors (see below), whose sum is σ = 43802944. Its totient is φ = 16426080.

The previous prime is 28745627. The next prime is 28745669. The reversal of 28745661 is 16654782.

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

It is not a de Polignac number, because 28745661 - 2⁶ = 28745597 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28745669) 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, 684400 + ... + 684441.

It is an arithmetic number, because the mean of its divisors is an integer number (5475368).

Almost surely, 2^28745661 is an apocalyptic number.

28745661 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

28745661 is a deficient number, since it is larger than the sum of its proper divisors (15057283).

28745661 is a wasteful number, since it uses less digits than its factorization.

28745661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1368851.

The product of its digits is 80640, while the sum is 39.

The square root of 28745661 is about 5361.4980182781. The cubic root of 28745661 is about 306.3308715481.

The spelling of 28745661 in words is "twenty-eight million, seven hundred forty-five thousand, six hundred sixty-one".