1621267690 has 16 divisors (see below), whose sum is σ = 3335179392. Its totient is φ = 555863184.

The previous prime is 1621267643. The next prime is 1621267691. The reversal of 1621267690 is 967621261.

It is a super-2 number, since 2×1621267690² = 5257017845275872200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1621267691) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11580414 + ... + 11580553.

It is an arithmetic number, because the mean of its divisors is an integer number (208448712).

Almost surely, 2^1621267690 is an apocalyptic number.

1621267690 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1621267690 is an abundant number, since it is smaller than the sum of its proper divisors (1713911702).

1621267690 is a wasteful number, since it uses less digits than its factorization.

1621267690 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23160981.

The product of its (nonzero) digits is 54432, while the sum is 40.

The square root of 1621267690 is about 40264.9685210358. The cubic root of 1621267690 is about 1174.7665605363.

The spelling of 1621267690 in words is "one billion, six hundred twenty-one million, two hundred sixty-seven thousand, six hundred ninety".