70011521 has 4 divisors (see below), whose sum is σ = 70522692. Its totient is φ = 69500352.

The previous prime is 70011499. The next prime is 70011541. The reversal of 70011521 is 12511007.

70011521 = T₃₆₆ + T₃₆₇ + ... + T₇₇₆.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 23280625 + 46730896 = 4825^2 + 6836^2 .

It is a cyclic number.

It is not a de Polignac number, because 70011521 - 2²⁶ = 2902657 is a prime.

It is a super-2 number, since 2×70011521² = 9803226145466882, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 70011521.

It is not an unprimeable number, because it can be changed into a prime (70011541) 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, 255380 + ... + 255653.

It is an arithmetic number, because the mean of its divisors is an integer number (17630673).

Almost surely, 2^70011521 is an apocalyptic number.

It is an amenable number.

70011521 is a deficient number, since it is larger than the sum of its proper divisors (511171).

70011521 is a wasteful number, since it uses less digits than its factorization.

70011521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 511170.

The product of its (nonzero) digits is 70, while the sum is 17.

The square root of 70011521 is about 8367.2887484537. The cubic root of 70011521 is about 412.1511388967.

Adding to 70011521 its reverse (12511007), we get a palindrome (82522528).

It can be divided in two parts, 700 and 11521, that added together give a palindrome (12221).

The spelling of 70011521 in words is "seventy million, eleven thousand, five hundred twenty-one".