75128343021 has 8 divisors (see below), whose sum is σ = 111301248960. Its totient is φ = 50085561996.

The previous prime is 75128343019. The next prime is 75128343089. The reversal of 75128343021 is 12034382157.

75128343021 is a `hidden beast` number, since 7 + 512 + 83 + 43 + 0 + 21 = 666.

It is not a de Polignac number, because 75128343021 - 2¹ = 75128343019 is a prime.

It is a super-3 number, since 3×75128343021³ (a number of 34 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (75128343221) 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, 1391265585 + ... + 1391265638.

It is an arithmetic number, because the mean of its divisors is an integer number (13912656120).

Almost surely, 2^75128343021 is an apocalyptic number.

It is an amenable number.

75128343021 is a deficient number, since it is larger than the sum of its proper divisors (36172905939).

75128343021 is a wasteful number, since it uses less digits than its factorization.

75128343021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2782531232 (or 2782531226 counting only the distinct ones).

The product of its (nonzero) digits is 40320, while the sum is 36.

The spelling of 75128343021 in words is "seventy-five billion, one hundred twenty-eight million, three hundred forty-three thousand, twenty-one".