70721643 has 8 divisors (see below), whose sum is σ = 94370256. Its totient is φ = 47110400.

The previous prime is 70721639. The next prime is 70721659. The reversal of 70721643 is 34612707.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 70721643 - 2² = 70721639 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 70721643.

It is not an unprimeable number, because it can be changed into a prime (70721603) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4578 + ... + 12743.

It is an arithmetic number, because the mean of its divisors is an integer number (11796282).

Almost surely, 2^70721643 is an apocalyptic number.

70721643 is a deficient number, since it is larger than the sum of its proper divisors (23648613).

70721643 is a wasteful number, since it uses less digits than its factorization.

70721643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18685.

The product of its (nonzero) digits is 7056, while the sum is 30.

The square root of 70721643 is about 8409.6161030097. The cubic root of 70721643 is about 413.5399274337.

The spelling of 70721643 in words is "seventy million, seven hundred twenty-one thousand, six hundred forty-three".