57078421 has 2 divisors, whose sum is σ = 57078422. Its totient is φ = 57078420.

The previous prime is 57078419. The next prime is 57078431. The reversal of 57078421 is 12487075.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 45037521 + 12040900 = 6711^2 + 3470^2 .

It is a cyclic number.

It is not a de Polignac number, because 57078421 - 2¹ = 57078419 is a prime.

It is a super-2 number, since 2×57078421² = 6515892287706482, which contains 22 as substring.

Together with 57078419, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (57078431) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 28539210 + 28539211.

It is an arithmetic number, because the mean of its divisors is an integer number (28539211).

Almost surely, 2^57078421 is an apocalyptic number.

It is an amenable number.

57078421 is a deficient number, since it is larger than the sum of its proper divisors (1).

57078421 is an equidigital number, since it uses as much as digits as its factorization.

57078421 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 15680, while the sum is 34.

The square root of 57078421 is about 7555.0262077639. The cubic root of 57078421 is about 385.0265254114.

The spelling of 57078421 in words is "fifty-seven million, seventy-eight thousand, four hundred twenty-one".