1438437421 has 2 divisors, whose sum is σ = 1438437422. Its totient is φ = 1438437420.

The previous prime is 1438437409. The next prime is 1438437467. The reversal of 1438437421 is 1247348341.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1395022500 + 43414921 = 37350^2 + 6589^2 .

It is a cyclic number.

It is not a de Polignac number, because 1438437421 - 2¹³ = 1438429229 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1438437521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 719218710 + 719218711.

It is an arithmetic number, because the mean of its divisors is an integer number (719218711).

Almost surely, 2^1438437421 is an apocalyptic number.

It is an amenable number.

1438437421 is a deficient number, since it is larger than the sum of its proper divisors (1).

1438437421 is an equidigital number, since it uses as much as digits as its factorization.

1438437421 is an evil number, because the sum of its binary digits is even.

The product of its digits is 64512, while the sum is 37.

The square root of 1438437421 is about 37926.7375475403. The cubic root of 1438437421 is about 1128.8346303992.

The spelling of 1438437421 in words is "one billion, four hundred thirty-eight million, four hundred thirty-seven thousand, four hundred twenty-one".