55139787 has 12 divisors (see below), whose sum is σ = 79933464. Its totient is φ = 36627360.

The previous prime is 55139783. The next prime is 55139797. The reversal of 55139787 is 78793155.

55139787 is a `hidden beast` number, since 551 + 3 + 97 + 8 + 7 = 666.

It is not a de Polignac number, because 55139787 - 2² = 55139783 is a prime.

It is a super-2 number, since 2×55139787² = 6080792220810738, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (55139783) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 8373 + ... + 13430.

It is an arithmetic number, because the mean of its divisors is an integer number (6661122).

Almost surely, 2^55139787 is an apocalyptic number.

55139787 is a deficient number, since it is larger than the sum of its proper divisors (24793677).

55139787 is a wasteful number, since it uses less digits than its factorization.

55139787 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22090 (or 22087 counting only the distinct ones).

The product of its digits is 264600, while the sum is 45.

The square root of 55139787 is about 7425.6169440660. The cubic root of 55139787 is about 380.6171573364.

The spelling of 55139787 in words is "fifty-five million, one hundred thirty-nine thousand, seven hundred eighty-seven".