12747777640 has 64 divisors (see below), whose sum is σ = 30916242000. Its totient is φ = 4702697472.

The previous prime is 12747777629. The next prime is 12747777659. The reversal of 12747777640 is 4677774721.

It can be written as a sum of positive squares in 8 ways, for example, as 7180528644 + 5567248996 = 84738^2 + 74614^2 .

It is a Harshad number since it is a multiple of its sum of digits (52).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 610086 + ... + 630634.

Almost surely, 2^12747777640 is an apocalyptic number.

12747777640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 12747777640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (15458121000).

12747777640 is an abundant number, since it is smaller than the sum of its proper divisors (18168464360).

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

12747777640 is a wasteful number, since it uses less digits than its factorization.

12747777640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21766 (or 21762 counting only the distinct ones).

The product of its (nonzero) digits is 3226944, while the sum is 52.

The spelling of 12747777640 in words is "twelve billion, seven hundred forty-seven million, seven hundred seventy-seven thousand, six hundred forty".