78026921 has 4 divisors (see below), whose sum is σ = 89173632. Its totient is φ = 66880212.

The previous prime is 78026917. The next prime is 78026951. The reversal of 78026921 is 12962087.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 78026921 - 2² = 78026917 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78026951) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5573345 + ... + 5573358.

It is an arithmetic number, because the mean of its divisors is an integer number (22293408).

Almost surely, 2^78026921 is an apocalyptic number.

It is an amenable number.

78026921 is a deficient number, since it is larger than the sum of its proper divisors (11146711).

78026921 is a wasteful number, since it uses less digits than its factorization.

78026921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11146710.

The product of its (nonzero) digits is 12096, while the sum is 35.

The square root of 78026921 is about 8833.2848363449. The cubic root of 78026921 is about 427.3150181757.

The spelling of 78026921 in words is "seventy-eight million, twenty-six thousand, nine hundred twenty-one".