72515170861057 has 4 divisors (see below), whose sum is σ = 72515218877140. Its totient is φ = 72515122844976.

The previous prime is 72515170861009. The next prime is 72515170861127. The reversal of 72515170861057 is 75016807151527.

It is a happy number.

It is a Cunningham number, because it is equal to 8515584²+1.

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 50655048279696 + 21860122581361 = 7117236^2 + 4675481^2 .

It is a cyclic number.

It is not a de Polignac number, because 72515170861057 - 2⁴³ = 63719077838849 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 72515170860989 and 72515170861007.

It is not an unprimeable number, because it can be changed into a prime (72515170861157) 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, 21666582 + ... + 24788527.

It is an arithmetic number, because the mean of its divisors is an integer number (18128804719285).

It is a Proth number, since it is equal to 4322241 ⋅ 2²⁴ + 1 and 4322241 < 2²⁴.

Almost surely, 2^{72515170861057} is an apocalyptic number.

It is an amenable number.

72515170861057 is a deficient number, since it is larger than the sum of its proper divisors (48016083).

72515170861057 is a wasteful number, since it uses less digits than its factorization.

72515170861057 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48016082.

The product of its (nonzero) digits is 4116000, while the sum is 55.

The spelling of 72515170861057 in words is "seventy-two trillion, five hundred fifteen billion, one hundred seventy million, eight hundred sixty-one thousand, fifty-seven".