15531046421 has 16 divisors (see below), whose sum is σ = 17203995648. Its totient is φ = 13901804400.

The previous prime is 15531046411. The next prime is 15531046499. The reversal of 15531046421 is 12464013551.

It is not a de Polignac number, because 15531046421 - 2⁶ = 15531046357 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 (15531046411) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2224466 + ... + 2231436.

It is an arithmetic number, because the mean of its divisors is an integer number (1075249728).

Almost surely, 2^15531046421 is an apocalyptic number.

15531046421 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

15531046421 is a deficient number, since it is larger than the sum of its proper divisors (1672949227).

15531046421 is a wasteful number, since it uses less digits than its factorization.

15531046421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10072.

The product of its (nonzero) digits is 14400, while the sum is 32.

Adding to 15531046421 its reverse (12464013551), we get a palindrome (27995059972).

The spelling of 15531046421 in words is "fifteen billion, five hundred thirty-one million, forty-six thousand, four hundred twenty-one".