1421666694 has 72 divisors (see below), whose sum is σ = 3680077320. Its totient is φ = 405636336.

The previous prime is 1421666683. The next prime is 1421666707. The reversal of 1421666694 is 4966661241.

It is a happy number.

It is a super-2 number, since 2×1421666694² = 4042272377657779272, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 1939152 + ... + 1939884.

It is an arithmetic number, because the mean of its divisors is an integer number (51112185).

Almost surely, 2^1421666694 is an apocalyptic number.

1421666694 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 1421666694, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1840038660).

1421666694 is an abundant number, since it is smaller than the sum of its proper divisors (2258410626).

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

1421666694 is an frugal number, since it uses more digits than its factorization.

1421666694 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1491 (or 745 counting only the distinct ones).

The product of its digits is 373248, while the sum is 45.

The square root of 1421666694 is about 37704.9956106615. The cubic root of 1421666694 is about 1124.4304459226.

The spelling of 1421666694 in words is "one billion, four hundred twenty-one million, six hundred sixty-six thousand, six hundred ninety-four".