155640761 has 8 divisors (see below), whose sum is σ = 166610400. Its totient is φ = 144948960.

The previous prime is 155640731. The next prime is 155640769. The reversal of 155640761 is 167046551.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-155640761 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (155640769) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 68300 + ... + 70541.

It is an arithmetic number, because the mean of its divisors is an integer number (20826300).

Almost surely, 2^155640761 is an apocalyptic number.

It is an amenable number.

155640761 is a deficient number, since it is larger than the sum of its proper divisors (10969639).

155640761 is a wasteful number, since it uses less digits than its factorization.

155640761 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 138919.

The product of its (nonzero) digits is 25200, while the sum is 35.

The square root of 155640761 is about 12475.6066385567. The cubic root of 155640761 is about 537.9077256836.

The spelling of 155640761 in words is "one hundred fifty-five million, six hundred forty thousand, seven hundred sixty-one".