79405981 has 8 divisors (see below), whose sum is σ = 80729600. Its totient is φ = 78090480.

The previous prime is 79405951. The next prime is 79405987. The reversal of 79405981 is 18950497.

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 79405981 - 2⁷ = 79405853 is a prime.

It is a super-2 number, since 2×79405981² = 12610619637144722, 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 (79405987) 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, 19555 + ... + 23263.

It is an arithmetic number, because the mean of its divisors is an integer number (10091200).

Almost surely, 2^79405981 is an apocalyptic number.

It is an amenable number.

79405981 is a deficient number, since it is larger than the sum of its proper divisors (1323619).

79405981 is a wasteful number, since it uses less digits than its factorization.

79405981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4059.

The product of its (nonzero) digits is 90720, while the sum is 43.

The square root of 79405981 is about 8911.0033666249. The cubic root of 79405981 is about 429.8178081593.

The spelling of 79405981 in words is "seventy-nine million, four hundred five thousand, nine hundred eighty-one".