75242749 has 4 divisors (see below), whose sum is σ = 77077980. Its totient is φ = 73407520.

The previous prime is 75242701. The next prime is 75242753. The reversal of 75242749 is 94724257.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 94724257 = 281 ⋅337097.

It can be written as a sum of positive squares in 2 ways, for example, as 35640900 + 39601849 = 5970^2 + 6293^2 .

It is a cyclic number.

It is not a de Polignac number, because 75242749 - 2⁷ = 75242621 is a prime.

It is a super-2 number, since 2×75242749² = 11322942554154002, which contains 22 as substring.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (75242789) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 917554 + ... + 917635.

It is an arithmetic number, because the mean of its divisors is an integer number (19269495).

Almost surely, 2^75242749 is an apocalyptic number.

It is an amenable number.

75242749 is a deficient number, since it is larger than the sum of its proper divisors (1835231).

75242749 is a wasteful number, since it uses less digits than its factorization.

75242749 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1835230.

The product of its digits is 141120, while the sum is 40.

The square root of 75242749 is about 8674.2578356883. The cubic root of 75242749 is about 422.1708258486.

The spelling of 75242749 in words is "seventy-five million, two hundred forty-two thousand, seven hundred forty-nine".