77161280 has 224 divisors, whose sum is σ = 231648000. Its totient is φ = 24385536.

The previous prime is 77161241. The next prime is 77161313. The reversal of 77161280 is 8216177.

It is a tau number, because it is divible by the number of its divisors (224).

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2085422 + ... + 2085458.

Almost surely, 2^77161280 is an apocalyptic number.

77161280 is a gapful number since it is divisible by the number (70) 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 77161280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (115824000).

77161280 is an abundant number, since it is smaller than the sum of its proper divisors (154486720).

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

77161280 is a wasteful number, since it uses less digits than its factorization.

77161280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 94 (or 70 counting only the distinct ones).

The product of its (nonzero) digits is 4704, while the sum is 32.

The square root of 77161280 is about 8784.1493612074. The cubic root of 77161280 is about 425.7289083199.

The spelling of 77161280 in words is "seventy-seven million, one hundred sixty-one thousand, two hundred eighty".