70720581 has 4 divisors (see below), whose sum is σ = 94294112. Its totient is φ = 47147052.

The previous prime is 70720549. The next prime is 70720597. The reversal of 70720581 is 18502707.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 70720581 - 2⁵ = 70720549 is a prime.

It is a super-2 number, since 2×70720581² = 10002801153955122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (70720511) 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, 11786761 + ... + 11786766.

It is an arithmetic number, because the mean of its divisors is an integer number (23573528).

Almost surely, 2^70720581 is an apocalyptic number.

It is an amenable number.

70720581 is a deficient number, since it is larger than the sum of its proper divisors (23573531).

70720581 is a wasteful number, since it uses less digits than its factorization.

70720581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23573530.

The product of its (nonzero) digits is 3920, while the sum is 30.

The square root of 70720581 is about 8409.5529607703. The cubic root of 70720581 is about 413.5378574327.

The spelling of 70720581 in words is "seventy million, seven hundred twenty thousand, five hundred eighty-one".