771222816 has 384 divisors, whose sum is σ = 2936424960. Its totient is φ = 191102976.

The previous prime is 771222811. The next prime is 771222841. The reversal of 771222816 is 618222177.

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

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (771222811) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1336320 + ... + 1336896.

It is an arithmetic number, because the mean of its divisors is an integer number (7646940).

Almost surely, 2^771222816 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 771222816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1468212480).

771222816 is an abundant number, since it is smaller than the sum of its proper divisors (2165202144).

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

771222816 is a wasteful number, since it uses less digits than its factorization.

771222816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 633 (or 619 counting only the distinct ones).

The product of its digits is 18816, while the sum is 36.

The square root of 771222816 is about 27770.8987251043. The cubic root of 771222816 is about 917.0505797880.

The spelling of 771222816 in words is "seven hundred seventy-one million, two hundred twenty-two thousand, eight hundred sixteen".