70725991 has 4 divisors (see below), whose sum is σ = 80829712. Its totient is φ = 60622272.

The previous prime is 70725971. The next prime is 70725997. The reversal of 70725991 is 19952707.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 19952707 = 23 ⋅867509.

It is a cyclic number.

It is not a de Polignac number, because 70725991 - 2⁵ = 70725959 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (70725997) 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, 5051850 + ... + 5051863.

It is an arithmetic number, because the mean of its divisors is an integer number (20207428).

Almost surely, 2^70725991 is an apocalyptic number.

70725991 is a deficient number, since it is larger than the sum of its proper divisors (10103721).

70725991 is a wasteful number, since it uses less digits than its factorization.

70725991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10103720.

The product of its (nonzero) digits is 39690, while the sum is 40.

The square root of 70725991 is about 8409.8746126206. The cubic root of 70725991 is about 413.5484021366.

The spelling of 70725991 in words is "seventy million, seven hundred twenty-five thousand, nine hundred ninety-one".