54997821 has 24 divisors (see below), whose sum is σ = 81186560. Its totient is φ = 35868096.

The previous prime is 54997819. The next prime is 54997823. The reversal of 54997821 is 12879945.

It is an interprime number because it is at equal distance from previous prime (54997819) and next prime (54997823).

It is not a de Polignac number, because 54997821 - 2¹ = 54997819 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (54997823) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 134265 + ... + 134673.

Almost surely, 2^54997821 is an apocalyptic number.

It is an amenable number.

54997821 is a deficient number, since it is larger than the sum of its proper divisors (26188739).

54997821 is a wasteful number, since it uses less digits than its factorization.

54997821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 705 (or 702 counting only the distinct ones).

The product of its digits is 181440, while the sum is 45.

The square root of 54997821 is about 7416.0515774905. The cubic root of 54997821 is about 380.2902238077.

The spelling of 54997821 in words is "fifty-four million, nine hundred ninety-seven thousand, eight hundred twenty-one".