690971506 has 4 divisors (see below), whose sum is σ = 1036457262. Its totient is φ = 345485752.

The previous prime is 690971473. The next prime is 690971509. The reversal of 690971506 is 605179096.

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

It can be written as a sum of positive squares in only one way, i.e., 549480481 + 141491025 = 23441^2 + 11895^2 .

It is not an unprimeable number, because it can be changed into a prime (690971509) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 172742875 + ... + 172742878.

Almost surely, 2^690971506 is an apocalyptic number.

690971506 is a deficient number, since it is larger than the sum of its proper divisors (345485756).

690971506 is a wasteful number, since it uses less digits than its factorization.

690971506 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 345485755.

The product of its (nonzero) digits is 102060, while the sum is 43.

The square root of 690971506 is about 26286.3368691798. The cubic root of 690971506 is about 884.0701208001.

It can be divided in two parts, 690 and 971506, that added together give a square (972196 = 986²).

The spelling of 690971506 in words is "six hundred ninety million, nine hundred seventy-one thousand, five hundred six".