21216040431 has 8 divisors (see below), whose sum is σ = 29200571904. Its totient is φ = 13687767960.

The previous prime is 21216040421. The next prime is 21216040519. The reversal of 21216040431 is 13404061212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21216040431 - 2¹⁷ = 21215909359 is a prime.

It is a super-2 number, since 2×21216040431² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21216040421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 114064641 + ... + 114064826.

It is an arithmetic number, because the mean of its divisors is an integer number (3650071488).

Almost surely, 2^21216040431 is an apocalyptic number.

21216040431 is a deficient number, since it is larger than the sum of its proper divisors (7984531473).

21216040431 is a wasteful number, since it uses less digits than its factorization.

21216040431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 228129501.

The product of its (nonzero) digits is 1152, while the sum is 24.

The spelling of 21216040431 in words is "twenty-one billion, two hundred sixteen million, forty thousand, four hundred thirty-one".