21719172429 has 24 divisors (see below), whose sum is σ = 31628156352. Its totient is φ = 14361580800.

The previous prime is 21719172413. The next prime is 21719172437. The reversal of 21719172429 is 92427191712.

It is a happy number.

21719172429 is a `hidden beast` number, since 2 + 1 + 71 + 91 + 72 + 429 = 666.

It is not a de Polignac number, because 21719172429 - 2⁴ = 21719172413 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21719172439) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 902734 + ... + 926480.

It is an arithmetic number, because the mean of its divisors is an integer number (1317839848).

Almost surely, 2^21719172429 is an apocalyptic number.

It is an amenable number.

21719172429 is a deficient number, since it is larger than the sum of its proper divisors (9908983923).

21719172429 is a wasteful number, since it uses less digits than its factorization.

21719172429 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24577 (or 24574 counting only the distinct ones).

The product of its digits is 127008, while the sum is 45.

The spelling of 21719172429 in words is "twenty-one billion, seven hundred nineteen million, one hundred seventy-two thousand, four hundred twenty-nine".