70723521 has 24 divisors (see below), whose sum is σ = 111724704. Its totient is φ = 42754560.

The previous prime is 70723511. The next prime is 70723537. The reversal of 70723521 is 12532707.

70723521 is a `hidden beast` number, since 70 + 72 + 3 + 521 = 666.

It is not a de Polignac number, because 70723521 - 2¹⁰ = 70722497 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (70723501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 57505 + ... + 58721.

It is an arithmetic number, because the mean of its divisors is an integer number (4655196).

Almost surely, 2^70723521 is an apocalyptic number.

It is an amenable number.

70723521 is a deficient number, since it is larger than the sum of its proper divisors (41001183).

70723521 is a wasteful number, since it uses less digits than its factorization.

70723521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1821 (or 1818 counting only the distinct ones).

The product of its (nonzero) digits is 2940, while the sum is 27.

The square root of 70723521 is about 8409.7277601597. The cubic root of 70723521 is about 413.5435878931.

The spelling of 70723521 in words is "seventy million, seven hundred twenty-three thousand, five hundred twenty-one".