54421891 has 4 divisors (see below), whose sum is σ = 54447552. Its totient is φ = 54396232.

The previous prime is 54421877. The next prime is 54421901. The reversal of 54421891 is 19812445.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 19812445 = 5 ⋅3962489.

It is a cyclic number.

It is not a de Polignac number, because 54421891 - 2¹⁹ = 53897603 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (54421091) 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, 9331 + ... + 13996.

It is an arithmetic number, because the mean of its divisors is an integer number (13611888).

Almost surely, 2^54421891 is an apocalyptic number.

54421891 is the 4666-th heptagonal number.

54421891 is a deficient number, since it is larger than the sum of its proper divisors (25661).

54421891 is a wasteful number, since it uses less digits than its factorization.

54421891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25660.

The product of its digits is 11520, while the sum is 34.

The square root of 54421891 is about 7377.1194242739. The cubic root of 54421891 is about 378.9581131785.

The spelling of 54421891 in words is "fifty-four million, four hundred twenty-one thousand, eight hundred ninety-one".