1240835657 has 2 divisors, whose sum is σ = 1240835658. Its totient is φ = 1240835656.

The previous prime is 1240835653. The next prime is 1240835681. The reversal of 1240835657 is 7565380421.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1212362761 + 28472896 = 34819^2 + 5336^2 .

It is a cyclic number.

It is not a de Polignac number, because 1240835657 - 2² = 1240835653 is a prime.

It is not a weakly prime, because it can be changed into another prime (1240835653) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 620417828 + 620417829.

It is an arithmetic number, because the mean of its divisors is an integer number (620417829).

Almost surely, 2^1240835657 is an apocalyptic number.

It is an amenable number.

1240835657 is a deficient number, since it is larger than the sum of its proper divisors (1).

1240835657 is an equidigital number, since it uses as much as digits as its factorization.

1240835657 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 201600, while the sum is 41.

The square root of 1240835657 is about 35225.4972569586. The cubic root of 1240835657 is about 1074.5783547775.

The spelling of 1240835657 in words is "one billion, two hundred forty million, eight hundred thirty-five thousand, six hundred fifty-seven".