1615064261 has 4 divisors (see below), whose sum is σ = 1615324524. Its totient is φ = 1614804000.

The previous prime is 1615064237. The next prime is 1615064273. The reversal of 1615064261 is 1624605161.

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 1000520161 + 614544100 = 31631^2 + 24790^2 .

It is a cyclic number.

It is not a de Polignac number, because 1615064261 - 2³⁰ = 541322437 is a prime.

It is a super-2 number, since 2×1615064261² = 5216865134318952242, which 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 (1615064161) 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, 120590 + ... + 133311.

It is an arithmetic number, because the mean of its divisors is an integer number (403831131).

Almost surely, 2^1615064261 is an apocalyptic number.

It is an amenable number.

1615064261 is a deficient number, since it is larger than the sum of its proper divisors (260263).

1615064261 is an equidigital number, since it uses as much as digits as its factorization.

1615064261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 260262.

The product of its (nonzero) digits is 8640, while the sum is 32.

The square root of 1615064261 is about 40187.8621103437. The cubic root of 1615064261 is about 1173.2663156794.

The spelling of 1615064261 in words is "one billion, six hundred fifteen million, sixty-four thousand, two hundred sixty-one".