21420069769 has 8 divisors (see below), whose sum is σ = 24979673600. Its totient is φ = 18360059508.

The previous prime is 21420069757. The next prime is 21420069793. The reversal of 21420069769 is 96796002412.

It is not a de Polignac number, because 21420069769 - 2⁷ = 21420069641 is a prime.

It is a super-2 number, since 2×21420069769² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21420069739) 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, 31224249 + ... + 31224934.

It is an arithmetic number, because the mean of its divisors is an integer number (3122459200).

Almost surely, 2^21420069769 is an apocalyptic number.

It is an amenable number.

21420069769 is a deficient number, since it is larger than the sum of its proper divisors (3559603831).

21420069769 is an frugal number, since it uses more digits than its factorization.

21420069769 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 62449204 (or 62449190 counting only the distinct ones).

The product of its (nonzero) digits is 326592, while the sum is 46.

It can be divided in two parts, 2142006 and 9769, that added together give a triangular number (2151775 = T₂₀₇₄).

The spelling of 21420069769 in words is "twenty-one billion, four hundred twenty million, sixty-nine thousand, seven hundred sixty-nine".