55651639 has 2 divisors, whose sum is σ = 55651640. Its totient is φ = 55651638.

The previous prime is 55651613. The next prime is 55651669. The reversal of 55651639 is 93615655.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-55651639 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (55651669) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27825819 + 27825820.

It is an arithmetic number, because the mean of its divisors is an integer number (27825820).

Almost surely, 2^55651639 is an apocalyptic number.

55651639 is a deficient number, since it is larger than the sum of its proper divisors (1).

55651639 is an equidigital number, since it uses as much as digits as its factorization.

55651639 is an evil number, because the sum of its binary digits is even.

The product of its digits is 121500, while the sum is 40.

The square root of 55651639 is about 7460.0026139406. The cubic root of 55651639 is about 381.7912636644.

The spelling of 55651639 in words is "fifty-five million, six hundred fifty-one thousand, six hundred thirty-nine".