77229421 has 2 divisors, whose sum is σ = 77229422. Its totient is φ = 77229420.

The previous prime is 77229391. The next prime is 77229431. The reversal of 77229421 is 12492277.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 43705321 + 33524100 = 6611^2 + 5790^2 .

It is a cyclic number.

It is not a de Polignac number, because 77229421 - 2⁵ = 77229389 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (77229431) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38614710 + 38614711.

It is an arithmetic number, because the mean of its divisors is an integer number (38614711).

Almost surely, 2^77229421 is an apocalyptic number.

It is an amenable number.

77229421 is a deficient number, since it is larger than the sum of its proper divisors (1).

77229421 is an equidigital number, since it uses as much as digits as its factorization.

77229421 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 14112, while the sum is 34.

The square root of 77229421 is about 8788.0271392389. The cubic root of 77229421 is about 425.8541916153.

The spelling of 77229421 in words is "seventy-seven million, two hundred twenty-nine thousand, four hundred twenty-one".