7147777421 has 2 divisors, whose sum is σ = 7147777422. Its totient is φ = 7147777420.

The previous prime is 7147777411. The next prime is 7147777433. The reversal of 7147777421 is 1247777417.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3970764196 + 3177013225 = 63014^2 + 56365^2 .

It is an emirp because it is prime and its reverse (1247777417) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 7147777421 - 2²⁶ = 7080668557 is a prime.

It is a super-2 number, since 2×7147777421² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (7147777411) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3573888710 + 3573888711.

It is an arithmetic number, because the mean of its divisors is an integer number (3573888711).

Almost surely, 2^7147777421 is an apocalyptic number.

It is an amenable number.

7147777421 is a deficient number, since it is larger than the sum of its proper divisors (1).

7147777421 is an equidigital number, since it uses as much as digits as its factorization.

7147777421 is an evil number, because the sum of its binary digits is even.

The product of its digits is 537824, while the sum is 47.

The square root of 7147777421 is about 84544.5292198141. The cubic root of 7147777421 is about 1926.2988857733.

The spelling of 7147777421 in words is "seven billion, one hundred forty-seven million, seven hundred seventy-seven thousand, four hundred twenty-one".