76221520 has 40 divisors (see below), whose sum is σ = 178861320. Its totient is φ = 30205440.

The previous prime is 76221511. The next prime is 76221539. The reversal of 76221520 is 2512267.

It can be written as a sum of positive squares in 4 ways, for example, as 4717584 + 71503936 = 2172^2 + 8456^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-2 number, since 2×76221520² = 11619440222220800, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4350 + ... + 13090.

It is an arithmetic number, because the mean of its divisors is an integer number (4471533).

Almost surely, 2^76221520 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 76221520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (89430660).

76221520 is an abundant number, since it is smaller than the sum of its proper divisors (102639800).

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

76221520 is a wasteful number, since it uses less digits than its factorization.

76221520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8863 (or 8857 counting only the distinct ones).

The product of its (nonzero) digits is 1680, while the sum is 25.

The square root of 76221520 is about 8730.4936859264. The cubic root of 76221520 is about 423.9935029264.

Adding to 76221520 its reverse (2512267), we get a palindrome (78733787).

The spelling of 76221520 in words is "seventy-six million, two hundred twenty-one thousand, five hundred twenty".