772240421 has 2 divisors, whose sum is σ = 772240422. Its totient is φ = 772240420.

The previous prime is 772240363. The next prime is 772240429. The reversal of 772240421 is 124042277.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 549902500 + 222337921 = 23450^2 + 14911^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-772240421 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (772240429) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 386120210 + 386120211.

It is an arithmetic number, because the mean of its divisors is an integer number (386120211).

Almost surely, 2^772240421 is an apocalyptic number.

It is an amenable number.

772240421 is a deficient number, since it is larger than the sum of its proper divisors (1).

772240421 is an equidigital number, since it uses as much as digits as its factorization.

772240421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6272, while the sum is 29.

The square root of 772240421 is about 27789.2141126733. The cubic root of 772240421 is about 917.4537426161.

Adding to 772240421 its reverse (124042277), we get a palindrome (896282698).

The spelling of 772240421 in words is "seven hundred seventy-two million, two hundred forty thousand, four hundred twenty-one".