155661269 has 2 divisors, whose sum is σ = 155661270. Its totient is φ = 155661268.

The previous prime is 155661211. The next prime is 155661277. The reversal of 155661269 is 962166551.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 79744900 + 75916369 = 8930^2 + 8713^2 .

It is a cyclic number.

It is not a de Polignac number, because 155661269 - 2¹⁶ = 155595733 is a prime.

It is a super-2 number, since 2×155661269² = 48460861333380722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (155661169) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 77830634 + 77830635.

It is an arithmetic number, because the mean of its divisors is an integer number (77830635).

Almost surely, 2^155661269 is an apocalyptic number.

It is an amenable number.

155661269 is a deficient number, since it is larger than the sum of its proper divisors (1).

155661269 is an equidigital number, since it uses as much as digits as its factorization.

155661269 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 97200, while the sum is 41.

The square root of 155661269 is about 12476.4285354423. The cubic root of 155661269 is about 537.9313504442.

The spelling of 155661269 in words is "one hundred fifty-five million, six hundred sixty-one thousand, two hundred sixty-nine".