52778921 has 8 divisors (see below), whose sum is σ = 57006600. Its totient is φ = 48575232.

The previous prime is 52778917. The next prime is 52778923. The reversal of 52778921 is 12987725.

It can be written as a sum of positive squares in 4 ways, for example, as 8410000 + 44368921 = 2900^2 + 6661^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 52778921 - 2² = 52778917 is a prime.

It is a super-2 number, since 2×52778921² = 5571229003848482, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (52778923) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1280 + ... + 10353.

It is an arithmetic number, because the mean of its divisors is an integer number (7125825).

Almost surely, 2^52778921 is an apocalyptic number.

It is an amenable number.

52778921 is a deficient number, since it is larger than the sum of its proper divisors (4227679).

52778921 is a wasteful number, since it uses less digits than its factorization.

52778921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11995.

The product of its digits is 70560, while the sum is 41.

The square root of 52778921 is about 7264.9102540912. The cubic root of 52778921 is about 375.1055608008.

The spelling of 52778921 in words is "fifty-two million, seven hundred seventy-eight thousand, nine hundred twenty-one".