70900721 has 4 divisors (see below), whose sum is σ = 70927872. Its totient is φ = 70873572.

The previous prime is 70900717. The next prime is 70900733. The reversal of 70900721 is 12700907.

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, and also an emirpimes, since its reverse is a distinct semiprime: 12700907 = 659 ⋅19273.

It is a cyclic number.

It is not a de Polignac number, because 70900721 - 2² = 70900717 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (70900741) 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, 9185 + ... + 15038.

It is an arithmetic number, because the mean of its divisors is an integer number (17731968).

Almost surely, 2^70900721 is an apocalyptic number.

It is an amenable number.

70900721 is a deficient number, since it is larger than the sum of its proper divisors (27151).

70900721 is a wasteful number, since it uses less digits than its factorization.

70900721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27150.

The product of its (nonzero) digits is 882, while the sum is 26.

The square root of 70900721 is about 8420.2565875394. The cubic root of 70900721 is about 413.8886819819. Note that the first 3 decimals are identical.

The spelling of 70900721 in words is "seventy million, nine hundred thousand, seven hundred twenty-one".