2139270421 has 4 divisors (see below), whose sum is σ = 2142738252. Its totient is φ = 2135802592.

The previous prime is 2139270409. The next prime is 2139270449. The reversal of 2139270421 is 1240729312.

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 1236928900 + 902341521 = 35170^2 + 30039^2 .

It is a cyclic number.

It is not a de Polignac number, because 2139270421 - 2⁵ = 2139270389 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 (2139270821) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1732990 + ... + 1734223.

It is an arithmetic number, because the mean of its divisors is an integer number (535684563).

Almost surely, 2^2139270421 is an apocalyptic number.

It is an amenable number.

2139270421 is a deficient number, since it is larger than the sum of its proper divisors (3467831).

2139270421 is an equidigital number, since it uses as much as digits as its factorization.

2139270421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3467830.

The product of its (nonzero) digits is 6048, while the sum is 31.

The square root of 2139270421 is about 46252.2477399748. The cubic root of 2139270421 is about 1288.5122806698.

Adding to 2139270421 its reverse (1240729312), we get a palindrome (3379999733).

The spelling of 2139270421 in words is "two billion, one hundred thirty-nine million, two hundred seventy thousand, four hundred twenty-one".