75649728 has 336 divisors, whose sum is σ = 275197824. Its totient is φ = 18063360.

The previous prime is 75649727. The next prime is 75649729. The reversal of 75649728 is 82794657.

It is an interprime number because it is at equal distance from previous prime (75649727) and next prime (75649729).

It is a tau number, because it is divible by the number of its divisors (336).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is not an unprimeable number, because it can be changed into a prime (75649723) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1759275 + ... + 1759317.

Almost surely, 2^75649728 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 75649728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (137598912).

75649728 is an abundant number, since it is smaller than the sum of its proper divisors (199548096).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

75649728 is a wasteful number, since it uses less digits than its factorization.

75649728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 100 (or 83 counting only the distinct ones).

The product of its digits is 846720, while the sum is 48.

The square root of 75649728 is about 8697.6852092956. The cubic root of 75649728 is about 422.9306147335.

Subtracting 75649728 from its reverse (82794657), we obtain a square (7144929 = 2673²).

The spelling of 75649728 in words is "seventy-five million, six hundred forty-nine thousand, seven hundred twenty-eight".