78121827 has 42 divisors (see below), whose sum is σ = 136314588. Its totient is φ = 44641044.

The previous prime is 78121819. The next prime is 78121843. The reversal of 78121827 is 72812187.

It is a happy number.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

It is not a de Polignac number, because 78121827 - 2³ = 78121819 is a prime.

It is a super-2 number, since 2×78121827² = 12206039707635858, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 78121791 and 78121800.

It is not an unprimeable number, because it can be changed into a prime (78121847) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 41 ways as a sum of consecutive naturals, for example, 11160258 + ... + 11160264.

Almost surely, 2^78121827 is an apocalyptic number.

78121827 is a deficient number, since it is larger than the sum of its proper divisors (58192761).

78121827 is an frugal number, since it uses more digits than its factorization.

78121827 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53 (or 10 counting only the distinct ones).

The product of its digits is 12544, while the sum is 36.

The square root of 78121827 is about 8838.6552710240. The cubic root of 78121827 is about 427.4881991202.

The spelling of 78121827 in words is "seventy-eight million, one hundred twenty-one thousand, eight hundred twenty-seven".