21212879763 has 6 divisors (see below), whose sum is σ = 28284176044. Its totient is φ = 14141751664.

The previous prime is 21212879731. The next prime is 21212879797. The reversal of 21212879763 is 36797821212.

It is a happy number.

It is not a de Polignac number, because 21212879763 - 2⁵ = 21212879731 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21212479763) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 210223 + ... + 294311.

Almost surely, 2^21212879763 is an apocalyptic number.

21212879763 is a deficient number, since it is larger than the sum of its proper divisors (7071296281).

21212879763 is an frugal number, since it uses more digits than its factorization.

21212879763 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 168181 (or 84092 counting only the distinct ones).

The product of its digits is 508032, while the sum is 48.

Multiplying 21212879763 by its sum of digits (48), we get a square (1018218228624 = 1009068²).

The spelling of 21212879763 in words is "twenty-one billion, two hundred twelve million, eight hundred seventy-nine thousand, seven hundred sixty-three".