78121097 has 16 divisors (see below), whose sum is σ = 82736640. Its totient is φ = 73672128.

The previous prime is 78121093. The next prime is 78121111. The reversal of 78121097 is 79012187.

It is a cyclic number.

It is not a de Polignac number, because 78121097 - 2² = 78121093 is a prime.

It is a super-2 number, since 2×78121097² = 12205811592966818, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78121093) 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, 290279 + ... + 290547.

It is an arithmetic number, because the mean of its divisors is an integer number (5171040).

Almost surely, 2^78121097 is an apocalyptic number.

It is an amenable number.

78121097 is a deficient number, since it is larger than the sum of its proper divisors (4615543).

78121097 is a wasteful number, since it uses less digits than its factorization.

78121097 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 520.

The product of its (nonzero) digits is 7056, while the sum is 35.

The square root of 78121097 is about 8838.6139750529. The cubic root of 78121097 is about 427.4868675788.

The spelling of 78121097 in words is "seventy-eight million, one hundred twenty-one thousand, ninety-seven".