70521553 has 4 divisors (see below), whose sum is σ = 71314020. Its totient is φ = 69729088.

The previous prime is 70521541. The next prime is 70521557. The reversal of 70521553 is 35512507.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 35512507 = 17 ⋅2088971.

It can be written as a sum of positive squares in 2 ways, for example, as 23503104 + 47018449 = 4848^2 + 6857^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-70521553 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (70521557) 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, 396100 + ... + 396277.

It is an arithmetic number, because the mean of its divisors is an integer number (17828505).

Almost surely, 2^70521553 is an apocalyptic number.

It is an amenable number.

70521553 is a deficient number, since it is larger than the sum of its proper divisors (792467).

70521553 is an equidigital number, since it uses as much as digits as its factorization.

70521553 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 792466.

The product of its (nonzero) digits is 5250, while the sum is 28.

The square root of 70521553 is about 8397.7111762670. The cubic root of 70521553 is about 413.1495548905.

The spelling of 70521553 in words is "seventy million, five hundred twenty-one thousand, five hundred fifty-three".