19086421 has 6 divisors (see below), whose sum is σ = 19722966. Its totient is φ = 18469800.

The previous prime is 19086409. The next prime is 19086451. The reversal of 19086421 is 12468091.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 10595025 + 8491396 = 3255^2 + 2914^2 .

It is not a de Polignac number, because 19086421 - 2⁷ = 19086293 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (31).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19086451) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 8970 + ... + 10891.

It is an arithmetic number, because the mean of its divisors is an integer number (3287161).

Almost surely, 2^19086421 is an apocalyptic number.

It is an amenable number.

19086421 is a deficient number, since it is larger than the sum of its proper divisors (636545).

19086421 is an equidigital number, since it uses as much as digits as its factorization.

19086421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19923 (or 19892 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 31.

The square root of 19086421 is about 4368.8008652261. The cubic root of 19086421 is about 267.2441248454.

The spelling of 19086421 in words is "nineteen million, eighty-six thousand, four hundred twenty-one".