1394432721 has 12 divisors (see below), whose sum is σ = 2197288080. Its totient is φ = 845110680.

The previous prime is 1394432693. The next prime is 1394432729. The reversal of 1394432721 is 1272344931.

It is a happy number.

It is not a de Polignac number, because 1394432721 - 2⁶ = 1394432657 is a prime.

It is a super-2 number, since 2×1394432721² = 3888885226790927682, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1394432729) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7042491 + ... + 7042688.

It is an arithmetic number, because the mean of its divisors is an integer number (183107340).

Almost surely, 2^1394432721 is an apocalyptic number.

1394432721 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1394432721 is a deficient number, since it is larger than the sum of its proper divisors (802855359).

1394432721 is a wasteful number, since it uses less digits than its factorization.

1394432721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14085196 (or 14085193 counting only the distinct ones).

The product of its digits is 36288, while the sum is 36.

The square root of 1394432721 is about 37342.1038641371. The cubic root of 1394432721 is about 1117.2041022500.

It can be divided in two parts, 13944 and 32721, that added together give a triangular number (46665 = T₃₀₅).

The spelling of 1394432721 in words is "one billion, three hundred ninety-four million, four hundred thirty-two thousand, seven hundred twenty-one".