1550697990 has 16 divisors (see below), whose sum is σ = 3721675248. Its totient is φ = 413519456.

The previous prime is 1550697989. The next prime is 1550697991. The reversal of 1550697990 is 997960551.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (1550697989) and next prime (1550697991).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1550697991) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 25844937 + ... + 25844996.

It is an arithmetic number, because the mean of its divisors is an integer number (232604703).

Almost surely, 2^1550697990 is an apocalyptic number.

1550697990 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1550697990 is an abundant number, since it is smaller than the sum of its proper divisors (2170977258).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1550697990 is a wasteful number, since it uses less digits than its factorization.

1550697990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51689943.

The product of its (nonzero) digits is 765450, while the sum is 51.

The square root of 1550697990 is about 39378.9028541934. The cubic root of 1550697990 is about 1157.4682173243.

The spelling of 1550697990 in words is "one billion, five hundred fifty million, six hundred ninety-seven thousand, nine hundred ninety".