78421783 has 16 divisors (see below), whose sum is σ = 88199712. Its totient is φ = 69120000.

The previous prime is 78421769. The next prime is 78421787. The reversal of 78421783 is 38712487.

It is a cyclic number.

It is not a de Polignac number, because 78421783 - 2⁹ = 78421271 is a prime.

It is a super-2 number, since 2×78421783² = 12299952097798178, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78421787) 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, 48183 + ... + 49783.

It is an arithmetic number, because the mean of its divisors is an integer number (5512482).

Almost surely, 2^78421783 is an apocalyptic number.

78421783 is a gapful number since it is divisible by the number (73) formed by its first and last digit.

78421783 is a deficient number, since it is larger than the sum of its proper divisors (9777929).

78421783 is a wasteful number, since it uses less digits than its factorization.

78421783 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1746.

The product of its digits is 75264, while the sum is 40.

The square root of 78421783 is about 8855.6074325819. The cubic root of 78421783 is about 428.0346272243.

The spelling of 78421783 in words is "seventy-eight million, four hundred twenty-one thousand, seven hundred eighty-three".