1523142421 has 6 divisors (see below), whose sum is σ = 1618009730. Its totient is φ = 1433545536.

The previous prime is 1523142419. The next prime is 1523142443. The reversal of 1523142421 is 1242413251.

It can be written as a sum of positive squares in 3 ways, for example, as 1153349521 + 369792900 = 33961^2 + 19230^2 .

It is not a de Polignac number, because 1523142421 - 2¹ = 1523142419 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 (1523142521) 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, 2634906 + ... + 2635483.

Almost surely, 2^1523142421 is an apocalyptic number.

It is an amenable number.

1523142421 is a deficient number, since it is larger than the sum of its proper divisors (94867309).

1523142421 is an equidigital number, since it uses as much as digits as its factorization.

1523142421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5270423 (or 5270406 counting only the distinct ones).

The product of its digits is 1920, while the sum is 25.

The square root of 1523142421 is about 39027.4572704910. The cubic root of 1523142421 is about 1150.5712149024.

Adding to 1523142421 its reverse (1242413251), we get a palindrome (2765555672).

The spelling of 1523142421 in words is "one billion, five hundred twenty-three million, one hundred forty-two thousand, four hundred twenty-one".