21699429729 has 8 divisors (see below), whose sum is σ = 28935740832. Its totient is φ = 14464702560.

The previous prime is 21699429709. The next prime is 21699429737. The reversal of 21699429729 is 92792499612.

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

It is not a de Polignac number, because 21699429729 - 2⁸ = 21699429473 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21699429709) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 363639 + ... + 419084.

It is an arithmetic number, because the mean of its divisors is an integer number (3616967604).

Almost surely, 2^21699429729 is an apocalyptic number.

It is an amenable number.

21699429729 is a deficient number, since it is larger than the sum of its proper divisors (7236311103).

21699429729 is an equidigital number, since it uses as much as digits as its factorization.

21699429729 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 791967.

The product of its digits is 8817984, while the sum is 60.

The spelling of 21699429729 in words is "twenty-one billion, six hundred ninety-nine million, four hundred twenty-nine thousand, seven hundred twenty-nine".