690888121 has 16 divisors (see below), whose sum is σ = 874229760. Its totient is φ = 530315280.

The previous prime is 690888091. The next prime is 690888151. The reversal of 690888121 is 121888096.

It is an interprime number because it is at equal distance from previous prime (690888091) and next prime (690888151).

It is not a de Polignac number, because 690888121 - 2⁹ = 690887609 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (690888151) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 61801 + ... + 72118.

It is an arithmetic number, because the mean of its divisors is an integer number (54639360).

Almost surely, 2^690888121 is an apocalyptic number.

It is an amenable number.

690888121 is a deficient number, since it is larger than the sum of its proper divisors (183341639).

690888121 is a wasteful number, since it uses less digits than its factorization.

690888121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 134004.

The product of its (nonzero) digits is 55296, while the sum is 43.

The square root of 690888121 is about 26284.7507311749. The cubic root of 690888121 is about 884.0345567902.

The spelling of 690888121 in words is "six hundred ninety million, eight hundred eighty-eight thousand, one hundred twenty-one".