1620086261 has 2 divisors, whose sum is σ = 1620086262. Its totient is φ = 1620086260.

The previous prime is 1620086233. The next prime is 1620086267. The reversal of 1620086261 is 1626800261.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1599520036 + 20566225 = 39994^2 + 4535^2 .

It is a cyclic number.

It is not a de Polignac number, because 1620086261 - 2¹⁰ = 1620085237 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1620086267) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 810043130 + 810043131.

It is an arithmetic number, because the mean of its divisors is an integer number (810043131).

Almost surely, 2^1620086261 is an apocalyptic number.

It is an amenable number.

1620086261 is a deficient number, since it is larger than the sum of its proper divisors (1).

1620086261 is an equidigital number, since it uses as much as digits as its factorization.

1620086261 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6912, while the sum is 32.

The square root of 1620086261 is about 40250.2951666196. The cubic root of 1620086261 is about 1174.4811376842.

The spelling of 1620086261 in words is "one billion, six hundred twenty million, eighty-six thousand, two hundred sixty-one".