77904481 has 2 divisors, whose sum is σ = 77904482. Its totient is φ = 77904480.

The previous prime is 77904443. The next prime is 77904487. The reversal of 77904481 is 18440977.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 40755456 + 37149025 = 6384^2 + 6095^2 .

It is a cyclic number.

It is not a de Polignac number, because 77904481 - 2¹³ = 77896289 is a prime.

It is a super-2 number, since 2×77904481² = 12138216319758722, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (77904487) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38952240 + 38952241.

It is an arithmetic number, because the mean of its divisors is an integer number (38952241).

Almost surely, 2^77904481 is an apocalyptic number.

It is an amenable number.

77904481 is a deficient number, since it is larger than the sum of its proper divisors (1).

77904481 is an equidigital number, since it uses as much as digits as its factorization.

77904481 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 56448, while the sum is 40.

The square root of 77904481 is about 8826.3515112418. The cubic root of 77904481 is about 427.0913866343.

The spelling of 77904481 in words is "seventy-seven million, nine hundred four thousand, four hundred eighty-one".