77731272 has 64 divisors (see below), whose sum is σ = 220968000. Its totient is φ = 25304832.

The previous prime is 77731271. The next prime is 77731301. The reversal of 77731272 is 27213777.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77731271) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5104 + ... + 13472.

It is an arithmetic number, because the mean of its divisors is an integer number (3452625).

Almost surely, 2^77731272 is an apocalyptic number.

77731272 is a gapful number since it is divisible by the number (72) 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 77731272, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (110484000).

77731272 is an abundant number, since it is smaller than the sum of its proper divisors (143236728).

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

77731272 is a wasteful number, since it uses less digits than its factorization.

77731272 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8427 (or 8417 counting only the distinct ones).

The product of its digits is 28812, while the sum is 36.

The square root of 77731272 is about 8816.5340128647. The cubic root of 77731272 is about 426.7746270856.

It can be divided in two parts, 7773 and 1272, that added together give a triangular number (9045 = T₁₃₄).

The spelling of 77731272 in words is "seventy-seven million, seven hundred thirty-one thousand, two hundred seventy-two".