155638477 has 2 divisors, whose sum is σ = 155638478. Its totient is φ = 155638476.

The previous prime is 155638433. The next prime is 155638487. The reversal of 155638477 is 774836551.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 149181796 + 6456681 = 12214^2 + 2541^2 .

It is an emirp because it is prime and its reverse (774836551) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-155638477 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (155638487) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 77819238 + 77819239.

It is an arithmetic number, because the mean of its divisors is an integer number (77819239).

Almost surely, 2^155638477 is an apocalyptic number.

It is an amenable number.

155638477 is a deficient number, since it is larger than the sum of its proper divisors (1).

155638477 is an equidigital number, since it uses as much as digits as its factorization.

155638477 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 705600, while the sum is 46.

The square root of 155638477 is about 12475.5150995861. The cubic root of 155638477 is about 537.9050944379.

The spelling of 155638477 in words is "one hundred fifty-five million, six hundred thirty-eight thousand, four hundred seventy-seven".