690481951 has 4 divisors (see below), whose sum is σ = 690593904. Its totient is φ = 690370000.

The previous prime is 690481949. The next prime is 690481993. The reversal of 690481951 is 159184096.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 690481951 - 2¹ = 690481949 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 690481898 and 690481907.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (690481921) 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, 46150 + ... + 59251.

It is an arithmetic number, because the mean of its divisors is an integer number (172648476).

Almost surely, 2^690481951 is an apocalyptic number.

690481951 is a deficient number, since it is larger than the sum of its proper divisors (111953).

690481951 is a wasteful number, since it uses less digits than its factorization.

690481951 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 111952.

The product of its (nonzero) digits is 77760, while the sum is 43.

The square root of 690481951 is about 26277.0232522636. The cubic root of 690481951 is about 883.8612828582.

The spelling of 690481951 in words is "six hundred ninety million, four hundred eighty-one thousand, nine hundred fifty-one".