78282421 has 8 divisors (see below), whose sum is σ = 89916800. Its totient is φ = 66760848.

The previous prime is 78282389. The next prime is 78282461. The reversal of 78282421 is 12428287.

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

It is not a de Polignac number, because 78282421 - 2⁵ = 78282389 is a prime.

It is a super-2 number, since 2×78282421² = 12256274875242482, 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 (78282461) 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, 26706 + ... + 29491.

It is an arithmetic number, because the mean of its divisors is an integer number (11239600).

Almost surely, 2^78282421 is an apocalyptic number.

It is an amenable number.

78282421 is a deficient number, since it is larger than the sum of its proper divisors (11634379).

78282421 is a wasteful number, since it uses less digits than its factorization.

78282421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56403.

The product of its digits is 14336, while the sum is 34.

The square root of 78282421 is about 8847.7353599664. The cubic root of 78282421 is about 427.7809258940.

The spelling of 78282421 in words is "seventy-eight million, two hundred eighty-two thousand, four hundred twenty-one".