1531324421 has 4 divisors (see below), whose sum is σ = 1670535744. Its totient is φ = 1392113100.

The previous prime is 1531324411. The next prime is 1531324423. The reversal of 1531324421 is 1244231351.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1244231351 = 11 ⋅113111941.

It is a cyclic number.

It is not a de Polignac number, because 1531324421 - 2⁶ = 1531324357 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1531324423) 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, 69605645 + ... + 69605666.

It is an arithmetic number, because the mean of its divisors is an integer number (417633936).

Almost surely, 2^1531324421 is an apocalyptic number.

1531324421 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1531324421 is a deficient number, since it is larger than the sum of its proper divisors (139211323).

1531324421 is a wasteful number, since it uses less digits than its factorization.

1531324421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 139211322.

The product of its digits is 2880, while the sum is 26.

The square root of 1531324421 is about 39132.1405113495. The cubic root of 1531324421 is about 1152.6277455436.

Adding to 1531324421 its reverse (1244231351), we get a palindrome (2775555772).

The spelling of 1531324421 in words is "one billion, five hundred thirty-one million, three hundred twenty-four thousand, four hundred twenty-one".