15420081 has 4 divisors (see below), whose sum is σ = 20560112. Its totient is φ = 10280052.

The previous prime is 15420079. The next prime is 15420103. The reversal of 15420081 is 18002451.

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 15420081 - 2¹ = 15420079 is a prime.

It is a super-2 number, since 2×15420081² = 475557796093122, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (15420011) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2570011 + ... + 2570016.

It is an arithmetic number, because the mean of its divisors is an integer number (5140028).

Almost surely, 2^15420081 is an apocalyptic number.

It is an amenable number.

15420081 is a deficient number, since it is larger than the sum of its proper divisors (5140031).

15420081 is an equidigital number, since it uses as much as digits as its factorization.

15420081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5140030.

The product of its (nonzero) digits is 320, while the sum is 21.

The square root of 15420081 is about 3926.8410968614. The cubic root of 15420081 is about 248.9022858154.

The spelling of 15420081 in words is "fifteen million, four hundred twenty thousand, eighty-one".