55152781 has 4 divisors (see below), whose sum is σ = 57550752. Its totient is φ = 52754812.

The previous prime is 55152739. The next prime is 55152793. The reversal of 55152781 is 18725155.

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 a cyclic number.

It is not a de Polignac number, because 55152781 - 2¹⁹ = 54628493 is a prime.

It is a super-2 number, since 2×55152781² = 6083658504067922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55153781) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1198951 + ... + 1198996.

It is an arithmetic number, because the mean of its divisors is an integer number (14387688).

Almost surely, 2^55152781 is an apocalyptic number.

It is an amenable number.

55152781 is a deficient number, since it is larger than the sum of its proper divisors (2397971).

55152781 is a wasteful number, since it uses less digits than its factorization.

55152781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2397970.

The product of its digits is 14000, while the sum is 34.

The square root of 55152781 is about 7426.4918366615. The cubic root of 55152781 is about 380.6470531773.

The spelling of 55152781 in words is "fifty-five million, one hundred fifty-two thousand, seven hundred eighty-one".