55507431 has 32 divisors (see below), whose sum is σ = 90616320. Its totient is φ = 29500416.

The previous prime is 55507429. The next prime is 55507433. The reversal of 55507431 is 13470555.

It is an interprime number because it is at equal distance from previous prime (55507429) and next prime (55507433).

It is not a de Polignac number, because 55507431 - 2¹ = 55507429 is a prime.

It is a super-2 number, since 2×55507431² = 6162149792439522, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55507433) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 30900 + ... + 32646.

It is an arithmetic number, because the mean of its divisors is an integer number (2831760).

Almost surely, 2^55507431 is an apocalyptic number.

55507431 is a gapful number since it is divisible by the number (51) formed by its first and last digit.

55507431 is a deficient number, since it is larger than the sum of its proper divisors (35108889).

55507431 is a wasteful number, since it uses less digits than its factorization.

55507431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1863.

The product of its (nonzero) digits is 10500, while the sum is 30.

The square root of 55507431 is about 7450.3309322472. The cubic root of 55507431 is about 381.4612046273.

Adding to 55507431 its reverse (13470555), we get a palindrome (68977986).

The spelling of 55507431 in words is "fifty-five million, five hundred seven thousand, four hundred thirty-one".