77140821 has 8 divisors (see below), whose sum is σ = 102924864. Its totient is φ = 51392000.

The previous prime is 77140801. The next prime is 77140837. The reversal of 77140821 is 12804177.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 77140821 - 2⁶ = 77140757 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77140801) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3180 + ... + 12821.

It is an arithmetic number, because the mean of its divisors is an integer number (12865608).

Almost surely, 2^77140821 is an apocalyptic number.

It is an amenable number.

77140821 is a deficient number, since it is larger than the sum of its proper divisors (25784043).

77140821 is a wasteful number, since it uses less digits than its factorization.

77140821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17611.

The product of its (nonzero) digits is 3136, while the sum is 30.

The square root of 77140821 is about 8782.9847432408. The cubic root of 77140821 is about 425.6912782303.

Adding to 77140821 its reverse (12804177), we get a palindrome (89944998).

The spelling of 77140821 in words is "seventy-seven million, one hundred forty thousand, eight hundred twenty-one".