77131280400 has 480 divisors, whose sum is σ = 260300304000. Its totient is φ = 19504742400.

The previous prime is 77131280399. The next prime is 77131280417. The reversal of 77131280400 is 408213177.

It is a happy number.

It is a super-2 number, since 2×77131280400² (a number of 23 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 517659526 + ... + 517659674.

It is an arithmetic number, because the mean of its divisors is an integer number (542292300).

Almost surely, 2^77131280400 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 77131280400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (130150152000).

77131280400 is an abundant number, since it is smaller than the sum of its proper divisors (183169023600).

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

77131280400 is a wasteful number, since it uses less digits than its factorization.

77131280400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 427 (or 416 counting only the distinct ones).

The product of its (nonzero) digits is 9408, while the sum is 33.

Adding to 77131280400 its reverse (408213177), we get a palindrome (77539493577).

The spelling of 77131280400 in words is "seventy-seven billion, one hundred thirty-one million, two hundred eighty thousand, four hundred".