77628309 has 16 divisors (see below), whose sum is σ = 116557824. Its totient is φ = 45529200.

The previous prime is 77628283. The next prime is 77628337. The reversal of 77628309 is 90382677.

It is not a de Polignac number, because 77628309 - 2⁷ = 77628181 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77628359) 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, 36919 + ... + 38964.

It is an arithmetic number, because the mean of its divisors is an integer number (7284864).

Almost surely, 2^77628309 is an apocalyptic number.

It is an amenable number.

77628309 is a deficient number, since it is larger than the sum of its proper divisors (38929515).

77628309 is a wasteful number, since it uses less digits than its factorization.

77628309 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 75928.

The product of its (nonzero) digits is 127008, while the sum is 42.

The square root of 77628309 is about 8810.6928785425. The cubic root of 77628309 is about 426.5861083124.

The spelling of 77628309 in words is "seventy-seven million, six hundred twenty-eight thousand, three hundred nine".