21777276246 has 64 divisors (see below), whose sum is σ = 50043847680. Its totient is φ = 6248219040.

The previous prime is 21777276197. The next prime is 21777276247. The reversal of 21777276246 is 64267277712.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21777276247) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2758621 + ... + 2766503.

It is an arithmetic number, because the mean of its divisors is an integer number (781935120).

Almost surely, 2^21777276246 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21777276246, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25021923840).

21777276246 is an abundant number, since it is smaller than the sum of its proper divisors (28266571434).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21777276246 is a wasteful number, since it uses less digits than its factorization.

21777276246 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10121.

The product of its digits is 2765952, while the sum is 51.

The spelling of 21777276246 in words is "twenty-one billion, seven hundred seventy-seven million, two hundred seventy-six thousand, two hundred forty-six".