77720523 has 16 divisors (see below), whose sum is σ = 105705600. Its totient is φ = 50780160.

The previous prime is 77720509. The next prime is 77720537. The reversal of 77720523 is 32502777.

It is an interprime number because it is at equal distance from previous prime (77720509) and next prime (77720537).

It is not a de Polignac number, because 77720523 - 2⁶ = 77720459 is a prime.

It is not an unprimeable number, because it can be changed into a prime (77720023) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 100683 + ... + 101451.

It is an arithmetic number, because the mean of its divisors is an integer number (6606600).

Almost surely, 2^77720523 is an apocalyptic number.

77720523 is a deficient number, since it is larger than the sum of its proper divisors (27985077).

77720523 is a wasteful number, since it uses less digits than its factorization.

77720523 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1402.

The product of its (nonzero) digits is 20580, while the sum is 33.

The square root of 77720523 is about 8815.9243984962. The cubic root of 77720523 is about 426.7549541285.

It can be divided in two parts, 77 and 720523, that added together give a triangular number (720600 = T₁₂₀₀).

The spelling of 77720523 in words is "seventy-seven million, seven hundred twenty thousand, five hundred twenty-three".