55732021 has 2 divisors, whose sum is σ = 55732022. Its totient is φ = 55732020.

The previous prime is 55732003. The next prime is 55732037. The reversal of 55732021 is 12023755.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 51279921 + 4452100 = 7161^2 + 2110^2 .

It is a cyclic number.

It is not a de Polignac number, because 55732021 - 2²¹ = 53634869 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (55732091) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27866010 + 27866011.

It is an arithmetic number, because the mean of its divisors is an integer number (27866011).

Almost surely, 2^55732021 is an apocalyptic number.

It is an amenable number.

55732021 is a deficient number, since it is larger than the sum of its proper divisors (1).

55732021 is an equidigital number, since it uses as much as digits as its factorization.

55732021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2100, while the sum is 25.

The square root of 55732021 is about 7465.3882015606. The cubic root of 55732021 is about 381.9749921953.

Adding to 55732021 its reverse (12023755), we get a palindrome (67755776).

The spelling of 55732021 in words is "fifty-five million, seven hundred thirty-two thousand, twenty-one".