501661511 has 8 divisors (see below), whose sum is σ = 540432144. Its totient is φ = 462916800.

The previous prime is 501661481. The next prime is 501661513. The reversal of 501661511 is 115166105.

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

It is a cyclic number.

It is not a de Polignac number, because 501661511 - 2¹⁰ = 501660487 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (501661513) 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, 56315 + ... + 64611.

It is an arithmetic number, because the mean of its divisors is an integer number (67554018).

Almost surely, 2^501661511 is an apocalyptic number.

501661511 is a deficient number, since it is larger than the sum of its proper divisors (38770633).

501661511 is a wasteful number, since it uses less digits than its factorization.

501661511 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12961.

The product of its (nonzero) digits is 900, while the sum is 26.

The square root of 501661511 is about 22397.8014769307. The cubic root of 501661511 is about 794.5787153901.

It can be divided in two parts, 5016615 and 11, that multiplied together give a triangular number (55182765 = T₁₀₅₀₅).

The spelling of 501661511 in words is "five hundred one million, six hundred sixty-one thousand, five hundred eleven".