15421861 has 8 divisors (see below), whose sum is σ = 18980864. Its totient is φ = 12201840.

The previous prime is 15421853. The next prime is 15421867. The reversal of 15421861 is 16812451.

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

It is not a de Polignac number, because 15421861 - 2³ = 15421853 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15421867) 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 7 ways as a sum of consecutive naturals, for example, 84645 + ... + 84826.

It is an arithmetic number, because the mean of its divisors is an integer number (2372608).

Almost surely, 2^15421861 is an apocalyptic number.

It is an amenable number.

15421861 is a deficient number, since it is larger than the sum of its proper divisors (3559003).

15421861 is a wasteful number, since it uses less digits than its factorization.

15421861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 169491.

The product of its digits is 1920, while the sum is 28.

The square root of 15421861 is about 3927.0677356012. The cubic root of 15421861 is about 248.9118627003.

It can be divided in two parts, 1542 and 1861, that added together give a triangular number (3403 = T₈₂).

The spelling of 15421861 in words is "fifteen million, four hundred twenty-one thousand, eight hundred sixty-one".