76421557 has 2 divisors, whose sum is σ = 76421558. Its totient is φ = 76421556.

The previous prime is 76421531. The next prime is 76421563. The reversal of 76421557 is 75512467.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 71250481 + 5171076 = 8441^2 + 2274^2 .

It is an emirp because it is prime and its reverse (75512467) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 76421557 - 2²³ = 68032949 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (76421507) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38210778 + 38210779.

It is an arithmetic number, because the mean of its divisors is an integer number (38210779).

Almost surely, 2^76421557 is an apocalyptic number.

It is an amenable number.

76421557 is a deficient number, since it is larger than the sum of its proper divisors (1).

76421557 is an equidigital number, since it uses as much as digits as its factorization.

76421557 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 58800, while the sum is 37.

The square root of 76421557 is about 8741.9424042944. The cubic root of 76421557 is about 424.3640907440.

The spelling of 76421557 in words is "seventy-six million, four hundred twenty-one thousand, five hundred fifty-seven".