615255132510661 has 4 divisors (see below), whose sum is σ = 615255231767500. Its totient is φ = 615255033253824.

The previous prime is 615255132510631. The next prime is 615255132510719. The reversal of 615255132510661 is 166015231552516.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 220647435890436 + 394607696620225 = 14854206^2 + 19864735^2 .

It is a cyclic number.

It is not a de Polignac number, because 615255132510661 - 2⁹ = 615255132510149 is a prime.

It is a super-2 number, since 2×615255132510661² (a number of 30 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (615255132510611) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 39663546 + ... + 52950043.

It is an arithmetic number, because the mean of its divisors is an integer number (153813807941875).

Almost surely, 2^{615255132510661} is an apocalyptic number.

It is an amenable number.

615255132510661 is a deficient number, since it is larger than the sum of its proper divisors (99256839).

615255132510661 is an equidigital number, since it uses as much as digits as its factorization.

615255132510661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 99256838.

The product of its (nonzero) digits is 1620000, while the sum is 49.

The spelling of 615255132510661 in words is "six hundred fifteen trillion, two hundred fifty-five billion, one hundred thirty-two million, five hundred ten thousand, six hundred sixty-one".