19790081 has 4 divisors (see below), whose sum is σ = 20061252. Its totient is φ = 19518912.

The previous prime is 19790063. The next prime is 19790101. The reversal of 19790081 is 18009791.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 10080625 + 9709456 = 3175^2 + 3116^2 .

It is a cyclic number.

It is not a de Polignac number, because 19790081 - 2¹⁴ = 19773697 is a prime.

It is a super-2 number, since 2×19790081² = 783294611973122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19790011) 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, 135476 + ... + 135621.

It is an arithmetic number, because the mean of its divisors is an integer number (5015313).

Almost surely, 2^19790081 is an apocalyptic number.

It is an amenable number.

19790081 is a deficient number, since it is larger than the sum of its proper divisors (271171).

19790081 is an equidigital number, since it uses as much as digits as its factorization.

19790081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 271170.

The product of its (nonzero) digits is 4536, while the sum is 35.

The square root of 19790081 is about 4448.6043878952. The cubic root of 19790081 is about 270.4887398322.

The spelling of 19790081 in words is "nineteen million, seven hundred ninety thousand, eighty-one".