75691521 has 12 divisors (see below), whose sum is σ = 110416020. Its totient is φ = 49960800.

The previous prime is 75691519. The next prime is 75691523. The reversal of 75691521 is 12519657.

75691521 is a `hidden beast` number, since 75 + 69 + 1 + 521 = 666.

It is an interprime number because it is at equal distance from previous prime (75691519) and next prime (75691523).

It can be written as a sum of positive squares in 2 ways, for example, as 72590400 + 3101121 = 8520^2 + 1761^2 .

It is not a de Polignac number, because 75691521 - 2¹ = 75691519 is a prime.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (75691523) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 40726 + ... + 42543.

It is an arithmetic number, because the mean of its divisors is an integer number (9201335).

Almost surely, 2^75691521 is an apocalyptic number.

It is an amenable number.

75691521 is a deficient number, since it is larger than the sum of its proper divisors (34724499).

75691521 is a wasteful number, since it uses less digits than its factorization.

75691521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83376 (or 83373 counting only the distinct ones).

The product of its digits is 18900, while the sum is 36.

The square root of 75691521 is about 8700.0874133540. The cubic root of 75691521 is about 423.0084836419.

It can be divided in two parts, 7569 and 1521, that multiplied together give a square (11512449 = 3393²).

The spelling of 75691521 in words is "seventy-five million, six hundred ninety-one thousand, five hundred twenty-one".