690515531 has 2 divisors, whose sum is σ = 690515532. Its totient is φ = 690515530.

The previous prime is 690515513. The next prime is 690515533. The reversal of 690515531 is 135515096.

It is a happy number.

Together with previous prime (690515513) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 690515531 - 2¹⁸ = 690253387 is a prime.

It is a super-2 number, since 2×690515531² = 953623397104423922, which contains 22 as substring.

It is a Sophie Germain prime.

Together with 690515533, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 690515491 and 690515500.

It is not a weakly prime, because it can be changed into another prime (690515533) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 345257765 + 345257766.

It is an arithmetic number, because the mean of its divisors is an integer number (345257766).

Almost surely, 2^690515531 is an apocalyptic number.

690515531 is a deficient number, since it is larger than the sum of its proper divisors (1).

690515531 is an equidigital number, since it uses as much as digits as its factorization.

690515531 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 20250, while the sum is 35.

The square root of 690515531 is about 26277.6622057595. The cubic root of 690515531 is about 883.8756108121.

The spelling of 690515531 in words is "six hundred ninety million, five hundred fifteen thousand, five hundred thirty-one".