75681409 has 4 divisors (see below), whose sum is σ = 75702016. Its totient is φ = 75660804.

The previous prime is 75681401. The next prime is 75681439. The reversal of 75681409 is 90418657.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 90418657 = 7 ⋅12916951.

It is a cyclic number.

It is not a de Polignac number, because 75681409 - 2³ = 75681401 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (75681401) 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, 3129 + ... + 12694.

It is an arithmetic number, because the mean of its divisors is an integer number (18925504).

Almost surely, 2^75681409 is an apocalyptic number.

It is an amenable number.

75681409 is a deficient number, since it is larger than the sum of its proper divisors (20607).

75681409 is a wasteful number, since it uses less digits than its factorization.

75681409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20606.

The product of its (nonzero) digits is 60480, while the sum is 40.

The square root of 75681409 is about 8699.5062503570. The cubic root of 75681409 is about 422.9896455465.

The spelling of 75681409 in words is "seventy-five million, six hundred eighty-one thousand, four hundred nine".