77218272 has 120 divisors (see below), whose sum is σ = 234666432. Its totient is φ = 24909120.

The previous prime is 77218259. The next prime is 77218277. The reversal of 77218272 is 27281277.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

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 (77218277) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 2490897 + ... + 2490927.

Almost surely, 2^77218272 is an apocalyptic number.

77218272 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 77218272, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (117333216).

77218272 is an abundant number, since it is smaller than the sum of its proper divisors (157448160).

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

77218272 is an frugal number, since it uses more digits than its factorization.

77218272 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 115 (or 36 counting only the distinct ones).

The product of its digits is 21952, while the sum is 36.

The square root of 77218272 is about 8787.3927873972. The cubic root of 77218272 is about 425.8336982298.

It can be divided in two parts, 772 and 18272, that added together give a square (19044 = 138²).

The spelling of 77218272 in words is "seventy-seven million, two hundred eighteen thousand, two hundred seventy-two".